(CNN) If Joe Biden maintains his steady lead in national polls over President Donald Trump through Election Day, Democrats will win the popular vote for the seventh time in the past eight presidential elections -- something no party has achieved since the formation of the modern American political system in 1828.
And yet, if Trump can restore his competitiveness in a handful of closely contested swing states, that might still not be enough for Biden to win the White House.
The prospect that Trump could win the Electoral College and the presidency while losing the popular vote a second time -- something no president has done -- underscores the extent to which the 2020 election is emerging as a stress test for a core pillar of American democracy: the belief that majorities, in most instances, should rule.
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In fact, over the past two decades, underlying features in the American electoral system that benefit small states, such as the Electoral College and the two-senator-per-state rule, have allowed Republicans to repeatedly win control of the federal government while a majority of voters preferred Democrats.
Though Republican nominees have won the popular vote only once in the five presidential elections since 2000, the GOP has controlled the White House for 12 of the 20 years since then. Similarly, Republicans have controlled the Senate more than half the time since 2000 even though GOP senators, when attributing half of each state's population to each senator, have never represented more people than their Democratic colleagues, according to calculations by Lee Drutman, a senior fellow at the think tank New America.
The American political system has long contained features designed to constrain the ability of majorities to impose their will -- what John Adams, among other founders, called "the tyranny of the majority." But the current situation is unusual in that it has consistently empowered a minority to drive the nation's agenda, notes Paul Pierson, a political scientist at the University of California at Berkeley.
"What's distinctive now is not that majorities have a hard time getting their way; it's that minorities have [the ability] to get their way," says Pierson, co-author with Yale political scientist Jacob Hacker of the recent book "Let Them Eat Tweets."
The most immediate question these imbalances raise may be whether the wave that is building against Trump and his allies is big enough to overcome the structural barriers that have entrenched Republican control of Washington. Hardly any operative in either party believes Trump has a realistic chance of winning the popular vote; but that doesn't mean he can't squeeze out another Electoral College win, as he did in 2016.
The longer-term question is whether faith in the American electoral system can survive a widening separation between voting preferences and electoral outcomes. More Americans will inevitably question the political system's legitimacy if it permits sustained rule by an electoral minority -- particularly one centered in the parts of the country least touched by the convulsive demographic, cultural and economic changes that are remaking American life.
But if Democrats achieve unified control of the White House and Congress in November, then pursue electoral revisions such as a new Voting Rights Act that make it more likely popular majorities will win control of government, that would likely spark a fierce backlash from Republican constituencies who already fear that the nation's underlying demographic changes are marginalizing them.
More turbulence is looming, either way.
"The legitimacy of elections is under tremendous fire," says Drutman. "The amount of litigation, of challenges, the attempts to game electoral laws, is through the roof. At a certain point, if the greatest enemy is the other party and nothing is seen as legitimate unless your side wins, you don't have that shared sense of fairness that democracy depends on."
In their book, Hacker and Pierson describe the divergence between popular majorities and electoral outcomes as "counter-majoritarianism, or sustained minority rule." By several key measures that divergence has widened over the past several decades -- in the process consistently benefiting Republicans, whose strength among non-college, Christian and non-urban White voters has allowed them to dominate in smaller, interior, heavily rural states.
Through 1996, just three presidents won the Electoral College and the presidency while losing the popular vote. But in this century, Trump in 2016 and George W. Bush in 2000 have already done that, and Trump might repeat the feat in 2020.
The frequency of these splits has obscured the magnitude of the contemporary shift toward Democrats in the presidential popular vote. A Biden popular vote win would mark the seventh time Democrats have captured the most votes in the eight elections since 1992. (Bush, in his 2004 reelection, is the only Republican who won the popular vote over this period.)
That's unprecedented. Since the formation of the modern party system in 1828, no party has won the popular vote more than six times over any eight-election sequence. Democrats did that from the 1820s to the 1850s, Republicans did it from the 1890s to the 1920s and Democrats managed the feat again from the 1930s to the 1960s. Viewed from another angle, no party has previously won seven popular-vote victories in fewer than nine presidential elections (as Democrats did from 1824 to 1856, Republicans from 1896 to 1928 and Democrats from 1932 to 1964).
Likewise, there's a tendency toward greater divergence -- and a Republican advantage -- in the most common metric used to assess imbalances in the Senate: counting the total population represented by each party by attributing half of each state's residents to each senator. From 1959 through 1980, Democrats held the Senate majority and also represented a majority of Americans in each Congress except the one that met from 1969 through 1970. Democrats continued to represent most Americans when they held the Senate majority from 1987 through 1994, during a brief period of control from mid-2001 through 2002 and again from 2007 through 2014, Drutman's calculations show.
But while the GOP has controlled the Senate for about 22 of the past 40 years, Republican senators have represented a majority of the nation's population for only a single session over that period: from 1997 to 1998.
Another measure underscores the imbalance. Molly Reynolds, a senior fellow in governance studies at the Brookings Institution, has calculated that the 47 current Democratic senators (including the two independents who caucus with the party) won a total of 69 million votes in their elections. That's 14 million more than the 55 million won by the 53 Senate Republicans who hold the majority.
The House of Representatives, based in smaller geographic areas, has been less influenced by these imbalances, but not immune to them. Over the past several decades, the party that won the most popular votes has almost always controlled the House majority, according to figures compiled in Brookings' Vital Statistics on Congress. (One conspicuous exception came in 2012, when Democrats narrowly beat the GOP in the total House popular vote, but the aggressive gerrymanders passed in many Republican-controlled states allowed the party to maintain the House majority.)
Even so, in every election when Republicans held the House majority since 1996, the party won a substantially larger share of the seats than it did of the popular vote, both because of its success in gerrymandering and because the Democrats' dominance of large urban centers results in them accumulating large numbers of "wasted" votes in landslide districts. (By contrast, in 2018 Democrats won 53% of the popular vote and 54% of the House seats.)
Even the Supreme Court isn't immune to these tendencies. As Hacker and Pierson note, all of the GOP-appointed justices that compose the conservative Supreme Court majority were selected by Republican presidents who lost the popular vote, except for Clarence Thomas, who was chosen by George H.W. Bush. In the cases of Brett Kavanaugh and Neil Gorsuch, not only were they selected by a President who lost the popular vote, they also were confirmed by senators who represented only 45% or less of the American population, according to calculations at the time. Even Thomas, as Hacker and Pierson point out, was confirmed by senators representing less than half the population.
"In other words," they write, "every one of these five conservative justices embody America's creeping counter-majoritarianism."
Many sociologists and political scientists expect the divergence between popular vote preferences and control of the government to continue to widen in the years ahead. The underlying population split between large and small states is certain to expand. Today, California, the most populous state, has nearly 70 times as many people as the least populous, Wyoming. A 2019 study of the Senate for the Roosevelt Institute cited demographic analyses projecting that by late in this century the largest state (Texas by then) will contain more than 150 times as many people as the smallest (Vermont). Yet under the current rules, each will still receive two senators.
Changes in political allegiance could compound the impact of that population shift. The Sun Belt behemoths of North Carolina, Florida, Georgia, Texas and Arizona have been among the big states where Republicans have competed most effectively: Trump won all of them in 2016 and the GOP controls all of their Senate seats except for one in Arizona. But increasing racial diversity and rising education levels are threatening the GOP hold on them all.
Those same factors have combined to produce growing deficits for Republicans, especially in the Trump era, in the big states along both coasts, such as New York, New Jersey, Massachusetts and Virginia in the East and California and Washington in the West. The only big states where the Republican position has improved recently are the larger Rust Belt states -- such as Ohio, Pennsylvania and Michigan -- that remain mostly White. Yet those states are shrinking as a share of the total national population.
These electoral patterns, combined with the population dynamics, could leave the GOP even more reliant on smaller states, and increase the odds that Democrats will win the most popular votes in presidential, House and Senate elections through the 2020s.
"It is certainly likely that Republicans will be even more dependent on small states in the near term given where the trends are going," says Drutman. "The likelihood of Republican senators representing a majority of the US population anytime soon seems incredibly unlikely unless there is a major partisan realignment."
Geoffrey Kabaservice, author of "Rule and Ruin," a history of moderate Republicans, and director of political studies at the libertarian Niskanen Center, notes that the systematic Republican moves in many states since 2010 to erect barriers to voting represent an implicit acknowledgment that the party is not now mustering majority support.
"The Republican appetite for vote suppression ultimately springs from the lack of confidence in the popular appeal of its ideas," he says. "Otherwise you wouldn't need to do that. ... I think the party has not just given up on ever winning majority status, it has given up on trying to persuade people who are not already in the camp."
One of the most consequential questions facing Democrats if they win unified control of Congress and the presidency in November will be how far to go in trying to reverse not only those state-level GOP barriers to voting, such as stringent voter-identification laws, but also the broader "counter-majoritarian" tendencies of the existing system.
Revising the two-senator-per-state rule or the Electoral College would require a constitutional amendment that is virtually guaranteed to fail. "For anything to happen you have to get a pretty good-sized bipartisan majority to amend the Constitution in any way," says Gary Jacobson, a University of California, San Diego, political scientist who specializes in Congress. "Since this has been to the Republicans' advantage, they are not about to give up that advantage."
Given the unlikelihood of constitutional amendments, most observers consider it more likely that a unified Democratic government would pursue the election agenda the House passed in 2019 -- and that former President Barack Obama recently endorsed in his eulogy for Rep. John Lewis. That would include approving a new Voting Rights Act, measures to ease registration and access to voting, limits on gerrymandering of congressional districts, constraints on unregulated political spending and potentially making the District of Columbia and Puerto Rico new states. (The House has already voted for DC statehood but has not addressed Puerto Rico.) Obama argued that passing such an agenda would even justify ending the Senate filibuster, a position echoed by a growing number of leaders in the racial justice movement.
Taken together, such an agenda might increase the chances that Democrats can win majorities in the House, Senate or Electoral College when they win the most votes in those contests. But any of those steps would likely infuriate the elements of the Republican base already most fearful that the country's cultural and demographic changes are eclipsing them. Sen. Tom Cotton may have previewed the debates ahead when the Arkansas Republican delivered what Brookings' Reynolds calls "a very thinly veiled racial argument" against DC statehood.
"A lot of Republican voters are already convinced that if Democrats take power, they are going to confiscate all their guns, shut down all their churches, force them to have transgender bathrooms everywhere," adds Drutman. "There is a very serious risk of a major insurrection if a lot of these folks feel they have no legitimate route to power because Democrats have taken that away."
Yet allowing a minority to consistently control the federal government also seems guaranteed to provoke turmoil. Sean Wilentz, a Princeton University historian who's the author of the encyclopedic book "The Rise of American Democracy," notes that James Madison, the Constitution's principal architect, feared not only a possible "tyranny of the majority" but also rule by a disciplined minority, like the wealthy financiers clustered around Alexander Hamilton.
"You see some of the framers understanding that both are problems," Wilentz says.
Before now, he notes, the period that saw the greatest concern about a minority dictating national policy was the final years before the Civil War. Through the 1850s, Northerners became increasingly convinced that a Southern "Slave Power" committed to slavery's expansion controlled the White House, the Senate and the Supreme Court, even though the North constituted a clear majority of the nation's population.
"A minority of the population seemed to run the federal government with the exception of the House of Representatives," Wilentz notes. Those concerns led to the formation of the Republican Party as an explicitly Northern coalition opposing slavery's spread and to the election of Abraham Lincoln in 1860, followed quickly by Southern secession and civil war.
Wilentz, like other analysts, isn't predicting a repeat of disunion for the 2020s. But he sees years of wrenching conflict ahead as Republicans try to hold power even as demographic change further reduces the odds that the party, as currently constituted, can assemble popular majorities, while Democrats seek changes in the electoral rules that allow the majority to govern.
"Who knows what is going to happen?" Wilentz says. "Rural America cannot secede from urban America. I think we'll be in historically uncharted waters ... and it scares the bejesus out of me."