(CNN) Early voting is up since the 2018 midterms across the country and in four of the six key states to watch for the 2022 midterms.
More than 41 million people have already voted in 47 states, according to data from election officials, Edison Research and Catalist. Mail-in voting was less common in 2018 and pre-election votes are still below the 2020 presidential election. Presidential elections typically see larger turnout and many states expanded early and mail-in voting for the Covid-19 pandemic.
Voters in Arizona, Georgia, Michigan and Pennsylvania have already cast more than 1 million ballots each. More than 2 million have voted early in Georgia, a 21% jump compared with this point in 2018.
Pre-election voters so far are generally slightly younger, more Democratic and diverse than they were in 2018, but not as much as they were in 2020.
Georgia, in particular, is seeing significant early voting turnout among Black voters. More than 125,000 more Black voters have cast ballots so far than at this point in 2018. So far Black voters make up the same share of Georgia's early electorate in 2018 and an even larger share than in 2020.
In addition to high Black voter turnout, the majority of Georgia early voters who didn't cast a ballot in 2018 are non-White. Nearly 40% of non-voters in the Peach State are a race or ethnicity other than White — a higher share than in any other key state.
There are nearly 18,000 more Asian Americans voting early and 14,000 more Latino early voters in Georgia than at this point in 2018. The most rapid growth in population in Georgia since 2010 has been among Asian Americans and Latinos, according to the US Census Bureau.
A similar share of White voters are casting ballots early in most of the six key states than at this point in the 2018 midterms.
The youngest voters — those aged 18-21 years — are showing up in higher numbers in all six key states compared to this point during the 2018 general election. The number of these youngest voters in Michigan has risen from fewer than 600 in 2018 — before absentee voting was available to all in the state — to nearly 26,000 so far this year. In every state, 18-21-year-old voters are roughly the same or a larger share of the electorate than even this time during the 2020 election.
One major contributing factor to higher early turnout among young voters, especially in Michigan and Pennsylvania, is that no-excuse voting by mail was introduced there in 2020.
"It's often the case that when you make voting easier, young people turn out more," said Charlotte Hill, the director of the Democracy Policy Initiative at UC-Berkeley's Goldman School of Public Policy. "That's because many steps of the voting process are disproportionately difficult for young people. When you make those steps easier, everyone benefits, but especially those people who had a harder time in the first place."
However, 18-21-year-old voters are still no more than 3% of the early vote in these key states.
Traditionally voters 65 and older make up a disproportionate share of a state's voters, Alan Abramowitz, a political scientist at Emory University, told CNN. This year is no exception. The largest age group of early voters in every state so far is senior citizens.
While there are fewer older voters who have voted early in each state than at this point in the last election, seniors are still a larger share of the early voting electorate than in 2020.
In those key states with available data — Arizona, Nevada and Pennsylvania — a slightly higher share of Democrats are turning out at this early stage in the general election than not only 2018, but 2020 as well. That includes Arizona, where Republican pre-election voters outnumbered Democrats at this point in 2018.
Independent voters are also turning out early in Arizona and Nevada, where roughly a quarter of all pre-election voters under 40 years old are independents. For Nevadans aged 18-21 years, the difference between Democrats and independents is roughly 7 percentage points.
The high Democratic turnout doesn't mean Democrats will sweep the general election, but likely signals a preference among Democrats for voting early and by mail.
"I think what we're seeing this year is just a continuation of the voting patterns that we saw in 2020," Abramowitz said.
Except among White voters and those older than 50 years in Arizona and Nevada, Democrats lead in early voting among all age and major race or ethnicity groups in all three states. However, a sizable number of pre-election voters in Arizona and Nevada are independents, which cuts into the Democratic share of the vote in those states. In Pennsylvania, more than 80% of non-White voters so far are Democrats. In Arizona and Nevada, however, roughly half of non-White voters are Democrats.
A large reason for that, at least in Nevada, has to do with the voter registration system, said Rebecca Gill, a political science professor at the University of Nevada, Las Vegas. Nevada adopted an automatic voter registration in 2020 where a voter is given the "nonpartisan" designation by default, she said.
"Only those highly motivated will take the extra steps, so making the extra step opting out instead of opting in yields a big increase in the number of folks in the program," Gill said.
"And if all those newly-registered nonpartisan voters had actively chosen to be nonpartisan, that might really say something about the current state of Nevada's electorate."