Almost half of early voters were in battleground states. Here's what we know about them

That's more than 48 million ballots cast ahead of Tuesday's election in key states, according to a survey of election officials by CNN, Edison Research, and Catalist.

Pre-Election Day voting surged this year as many voters were energized to cast a ballot ahead of November 3, mobilized by concerns about the ongoing coronavirus pandemic and heightened attention to the presidential race. It's not clear whether the increase signaled a massive turnout wave or represented voters who otherwise would have voted on Tuesday.

The increases were especially significant among voters under 30. Detailed voter information comes from Catalist, a company that provides data, analytics and other services to Democrats, academics and nonprofit issue-advocacy organizations and is giving insights into who is voting before November.

The data are not predictive of ultimate outcomes. Democrats nationwide have shown a preference to cast their ballots before Election Day, while many Republicans strongly prefer to vote Tuesday in person, according to recent polls.

Here is what we know about who has already voted in the key states that could decide who will become the next president.

Arizona

The parties head into Election Day tied with ballots already cast. Democrats and Republicans each make up 37% of pre-election voters. Four years ago, Republicans had a five-point edge in the pre-election vote and a four-point lead in the final exit polls. About one-third of the state's registered voters are not currently affiliated with either party.

Younger voters make up 13% of Arizona's early voters so far. That's almost double what it was at this point four years ago. According to exit polls, 14% of Arizona voters overall were under 30 in 2016. This could mean that younger voters are poised to make a larger share of the vote overall, or that more they chose to vote early.

Hispanic voters have expanded their share of ballots already cast from nearly 14% last cycle to 16% now. About 73% of ballots already cast have come from White voters, down more than three percentage points from this point in 2016. Exit polls showed Latino voters comprised about 15% of the state's total electorate in 2016.

Colorado

Democrats started Tuesday with a five-point lead over Republicans in pre-election voters, 33% to 28%. Four years ago, they were tied at 33%, but the exit polls show Republicans made up 24% after voting ended.

Younger voters have almost doubled their share of early voters in Colorado, where they went from 8% in 2016 to 14% now. That's below the 19% share of the total electorate that were voters under 30 in 2016, according to exit polls.

The vast majority of ballots cast in Colorado -- 81% -- have come from White voters, although this is a small decrease from 83% this time four years ago. Hispanic voters account for the second largest share of early votes at 10%, up two percentage points from 2016. Exit polls from last cycle show Latino voters comprised about 12% of the state's overall 2016 electorate.

Florida

Florida's 2020 pre-Election Day vote tells a similar story to most Presidential voting in the Sunshine State -- it's close. Democrats have a one-point edge over Republicans in pre-election votes. Four years ago, that gap was two-points. Exit polls showed a one-point lead for Republicans after Election Day voting, on par with the final results.

Voters in Florida under 30 made up 12% of the early vote. That's up significantly from Election Day 2016, when they made up 7% of pre-election voters. Like in Colorado, younger voters made up an even larger share of Florida's total electorate in 2016, according to exit polls, suggesting more of those young voters may vote in person on Election Day.

Both campaigns have focused their efforts on courting Hispanic voters in the Sunshine State. They currently represent almost 17% of early voters -- the second largest share of voters behind White voters at roughly 66%. In 2016, Latino voters made up approximately 18% of Florida's voters overall, according to exit polls.

About 55% of ballots already cast have come from women, and about 45% from men -- roughly on par with this point four years ago. Exit polls, however, showed Florida's total electorate was about 53% women and 47% men. If this current trend continues, it could signal increased turnout among women in Florida -- or it might just be indicative of more women choosing to vote early.

Georgia

Georgia's early voting electorate was pretty similar to that of four years ago. Black voters account for about 30% of early votes so far -- the largest share of early votes from Black voters in all of the key states for which Catalist has data on race. White voters, meanwhile, account for about 62% of ballots so far, a three-point decrease from this time four years ago. Overall, exit polls showed Georgia's total electorate was 60% White and 30% Black in the 2016 election.

About 15% of early voters in Georgia so far are under 30, a significant increase from 8% before Election Day 2016. Younger voters made up 18% of Georgia's total electorate in 2016, according exit polls, so we might expect more younger voters to vote at the polls today.

Iowa

Democrats went into Election Day with a stronger lead among pre-election voters than 2016. Currently, 46% of those voters are Democrats, 13 points higher than Republicans. Four years ago, they had a nine-point edge in pre-election turnout. After Election Day voting, exit polls show Republicans had a three-point lead over Democrats. Trump ultimately won the state. The largest bloc in the exit polls came from independents, who made up 35% of the vote in 2016.

Younger voters make up a larger share of Iowa's early voters this year than in 2016, but the change isn't as dramatic as in some other key battlegrounds. Voters under 30 make up 12% of early voters in Iowa, up from 8% four years ago at this time. 18% of Iowa's total 2016 electorate were voters under 30, according to exit polls.

Michigan

Voters under 30 have more than tripled their share of the pre-election vote compared to this time in 2016. Currently, they make up about 10% of those ballots. After in-person voting finished in 2016, younger voters accounted for 21% of the total electorate, according to exit polls, so despite the large uptick in early voting among the group, many of them may still turn out.

Michigan's early voters were more diverse than they were at this point in the cycle four years ago. Black voters have expanded their share of pre-Election Day votes from almost 9% at this time in 2016 to more than 12% currently. In 2016, exit polls showed Black voters represented about 15% of Michigan's overall electorate.

About 56% of early votes in Michigan were cast by women, a slight decrease from about 58% at this time in 2016. Exit polls, however, showed Michigan's total 2016 electorate was comprised of about 52% women. The large early vote turnout from Michigan women so far could signal increased turnout overall this cycle or a redistribution of those who decided to vote early instead of on Election Day.

Minnesota

About 13% of Minnesota's early voters have been under 30. That's more than twice 2016's pre-election figure. Voters under 30 made up 19% of Minnesota's overall electorate four years ago, according to exit polls.

White voters made up most of Minnesota's early voters so far, although this is a smaller percentage than four years ago. At this time in 2016, 92% of ballots already cast came from White voters; now it's about 88%. Black voters, Asian voters and Hispanic voters have seen about one percentage-point upticks in each of their shares of the pre-Election Day vote so far.

Nevada

Democrats once again held a 5-point lead in the pre-election vote. That's the same lead as four years ago. Ultimately, exit polls show Democrats led Republicans by eight points of the vote in the state. Trump lost by less than three points here.

Some 13% of early voters in Nevada have been under 30 -- a share that was up significantly from 8% at this point in 2016. It's also up 2 points from a week ago.

About two-thirds of ballots already cast in Nevada have come from White voters, down almost three percentage points from this time four years ago. Hispanic voters account for the second largest share of Nevada's pre-Election Day votes at 14% -- about the same as this point in 2016. Exit polls last cycle showed Latino voters comprised 18% of the state's overall electorate.

North Carolina

Democrats led Republicans in pre-election turnout by six points, down from eight points at this time in 2016. Election Day voting made a big difference in the state last cycle. The Democratic lead in ballots cast in 2016 exit polls narrowed to four points over Republicans. Exit polls also showed one-third of voters identified as independent, and President Trump won more than half of that vote, leading him to victory in the state.

Some 15% of North Carolina's early voters were under 30, the largest share of any of these key states. That share was significantly higher than it was before Election Day 2016, when it was only 8%. In 2016, 18% of North Carolina's total electorate was under 30, according to exit polls, so we'll see if strong turnout among that group continues on election day.

Black voters currently account for 21% of North Carolina's ballots already cast -- a small decrease from nearly 23% four years ago -- but still the second largest share of early voters in the state. This is roughly on par with North Carolina's overall electorate in 2016, when 20% of the state's total voters were Black, according to exit polls.

Ohio

Some 12% of early voters in Ohio have been under 30. That was up from 7% four years ago. Voters 30-64 also went up from 46% of early voters in 2016 to 53% now, with a decrease in voters over the age of 65. In total, younger voters made up 18% of the 2016 vote, while voters age 30-64 made up 63%, according to exit polls.

The breakdown of Ohio's early voters by race was identical to that of this time four years ago -- White voters make up about 86% of early voters, followed by Black voters at 11%, Hispanic voters at 2% and Asian voters at 1%.

Pennsylvania

In Pennsylvania, voters under 30 account for 13% of votes cast so far. That hasn't changed much in the last week but it's still below those voters' 16% share of the total 2016 electorate, according to exit polls.

The state expanded mail voting to all voters this year for the first time. Democrats have taken advantage of it by 42 points, but polling in the state and nationwide shows Republicans prefer to cast their ballots on Election Day in person. 2016 exit polls showed Democrats led Republicans 42%-39%. Trump won Republicans and independents, who accounted for 20% of the vote.

The vast majority -- 82% -- of ballots already cast in the Keystone State come from White voters, and Black voters account for the second largest share at 11%. This is remarkably similar to 2016 exit polls, which showed Pennsylvania's total electorate was about 81% White and 10% Black.

At almost 57%, the share of pre-election ballots cast by women in Pennsylvania is the largest of all the key states for which Catalist has data on gender. This is also outpacing the state's 2016 exit polls, which showed Pennsylvania's overall electorate was 53% women - a sign of either a massive turnout wave this cycle or perhaps more women in the state deciding to vote early who would've otherwise voted on Election Day.

Texas

Younger Texans doubled their share of early voters from 7% before Election Day in 2016 to about 15% now. Turnout on Tuesday will determine if younger voters will make up a larger share of Texas' overall electorate than the 18% they were in 2016, per exit polls.

Texas had one of the most diverse early voting electorates of the competitive states where race data is available from Catalist. Almost 22% of early votes in Texas have come from Hispanic voters -- the largest share from Hispanic voters of these key states. About 59% of early votes come from White voters, which is the smallest share from White voters in the key states. Black voters account for about 13% of early voters, which is a slight decrease from this point in 2016.

Exit polls from 2016 showed the breakdown of Texas' total electorate was similar to this pre-Election Day breakdown -- 57% White, 24% Latino and 11% Black.

Wisconsin

Wisconsin saw a large decrease in the share of early votes from people 65 or older. Seniors went from 46% of the early vote in 2016 to 33% now. Voters under 30 made up only 4% of pre-Election Day voters four years ago but now make up 6%. More voters' ages are unknown this cycle than four years ago. Exit polls put younger voters' share of Wisconsin's total electorate at 17% in 2016, so larger turnout among these voters on Election Day would not be surprising.

By race, the breakdown of Wisconsin's early voters was very similar to this point in 2016, with White voters accounting for most of the ballots already cast at 88%. Black voters comprise the second highest share of pre-election ballots at just over 5%. Last cycle, Wisconsin's total electorate was about 86% White and 7% Black, according to exit polls.

Almost 55% of ballots cast so far have come from women in Wisconsin. In 2016, women comprised just over half -- 51% -- of the state's overall turnout, according to exit polls.