Editor's Note: (Julian Zelizer is a professor of history and public affairs at Princeton University and a New America fellow. He is the author of "Jimmy Carter" and "The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society." The opinions expressed in this commentary are his.)
(CNN) Some Democrats are giddy about the possibility of Donald Trump winning the Republican nomination. They see him as the perfect antidote to the many gains Republicans have made over the past decade in state and congressional politics.
But other Democrats, including former President Bill Clinton, fear Trump could prove a formidable general election opponent. A recent CNN/ORC Poll shows that both Democratic candidates would do well against Trump in the general election, but Trump has confounded expectations before.
With Trump, the optimists believe, Republicans might have another Barry Goldwater on their hands. This is a reference to the right-wing Arizona senator who ran in 1964 against President Lyndon Johnson, urging his party to embrace conservatism and leave behind the moderate elements who were so powerful in the party.
When Republicans met at their convention at the Cow Palace in San Francisco in July 1964, delegates booed New York Gov. Nelson Rockefeller when he warned against extremists who played on "fear, hate and terror." They roared with approval when Goldwater responded: "Extremism in the defense of liberty is no vice. Moderation in the pursuit of justice is no virtue."
The GOP's choice turned out to be a total disaster: Johnson ran a devastating campaign that effectively portrayed Goldwater as far off center. The most famous attack came with the "Daisy" television ad, which showed a girl picking the petals off a daisy as a male voice counted down from 10 to 1. The ad ended as the camera zoomed in on her eyes and a massive nuclear explosion filled the screen.
In another ad, which might be brought back in 2016 if Trump wins, viewers saw Ku Klux Klan members marching in their regalia and burning crosses, a reference to an endorsement Goldwater received from a leader of the Alabama Ku Klux Klan.
Johnson won re-election by a massive landslide with 486 electoral votes to Goldwater's 52. Johnson's popular vote, 61%, was the biggest in American history, bigger than FDR in 1936. Just as bad, the Goldwater effect was devastating to congressional candidates for the GOP, including in stalwart Republican areas such as the Midwest, where a "frontlash" developed against the nominee, with votes flipping from the GOP to the Democrats.
Democrats exited the election with 295 seats in the House and 68 in the Senate, huge majorities that set up the perfect conditions for passage of transformative social programs like Medicare and Medicaid, the Voting Rights Act, and federal assistance to schools. Goldwater's promise was to move American politics to the right, but in the end, his nomination did the opposite.
But will a Trump candidacy be a repeat of 1964? That outcome is far from clear.
The biggest difference between then and now is the polarization of the electorate. Over the past few election cycles, there has been remarkably little movement of voters between parties in most states. The states themselves have been predictably red or blue, with presidential elections usually being decided by a handful of states including Ohio, Florida and Colorado.
In addition, the Republican Party has moved far to the right over the past few decades. Some controversial statements that got Goldwater in trouble in 1964 would now find support in red parts of the country. On the most controversial issues, like his hard-line stance against immigration and his incessant attacks on "political correctness," Trump is not as much of an outlier as Goldwater was perceived to be in 1964.
And there is little evidence to suggest that a Trump candidacy would allow Democrats to make huge gains in the House, the base of conservative power. Republicans have a solid hold in the gerrymandered districts where the electorate is blood red and where there is little chance of a Democrat succeeding. The only opponents who have a chance are those who are even more conservative than current officeholders.
The best opportunity would be for Democrats to win control of the Senate, given that there are a number of competitive seats where a Trump candidacy could make a difference. Winning the Senate, probably by narrow margins at best, would certainly be important. But with Republicans solidly on top of the House, this would not be another landslide.
Trump is also a very different kind of candidate than Goldwater. Goldwater's candidacy grew out of a growing conservative movement that had a clear set of principles: limited government, strong anti-communism, and opposition to federal civil rights legislation. By seizing on those principles, Johnson was able to develop a powerful argument against clear positions that depicted Goldwater as too far to the right.
Trump's campaign, on the other hand, is far more about style than actual policy. While he has given some fodder for attacks against right wing positions and affiliations -- particularly remarks about Muslims and ambiguous comments about former KKK Grand Wizard David Duke -- on many issues, he has simply not articulated a clear position, making him more difficult to attack than Goldwater.
On issues he has spoken about --- such as his comments about tax increases and health care and free trade -- he is often as likely to land on the left side of an issue as the right. But thus far, this has not seemed to hurt Trump. Republicans, including evangelicals, have repeatedly shown themselves willing to support him notwithstanding some of his less conservative stances.
Though Goldwater was an effective senator, he was a terrible campaigner, constantly stumbling over his words and making statements that didn't play well with the media. According to one Johnson adviser, Goldwater "scattered his shots too widely, hit too many issues, and thus diffused his impact." And, "On the big issues," he added, "he scared people."
Trump, by contrast, is extremely effective with the media. He seems to have a genuine feel for articulating the anger that exists in the electorate and a knack for making controversial statements that garner lots of attention, but packaging them in a way that insulate him from attack.
Americans seem to want more Trump, not less.
It's also important to remember that when Goldwater ran, Democrats were in good shape: The death of a popular Democratic president, John F. Kennedy, had been devastating to many Americans and was still very much on the mind of the electorate and LBJ very clearly connected his candidacy to this popular president.
In this general election, the connection will be more problematic for Hillary Clinton, given Obama's middling approval ratings. Johnson, who replaced JFK and was running for re-election, also had a pretty good year. LBJ's approval ratings would reach a whopping 80% in March 1964. Vietnam was still not a serious issue, and Congress had passed a number of his major proposals, including the Civil Rights Act of 1964 and the War on Poverty.
Democrats should thus be careful in thinking through what a Trump candidacy might mean. While it is possible to envision a repeat of 1964, it is also easy to see why this election might be very different.
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