If trends continue, turnout could beat the 49% recorded in 1966, a number that has not been surpassed since in a midterm

Early voter turnout is surging in several key states, suggesting more Americans may cast their ballots in next week’s midterm elections compared to previous years.

In Georgia, where a razor-thin governor’s race has been roiled by accusations of voter suppression, turnout has been huge, the Atlanta Journal Constitution reported. On the first day of early voting this month, turnout was triple that of 2014: 69,049 people cast ballots, up from 20,898.

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Last Saturday, the wait to vote at the main election office in Cobb county stretched to three to four hours, the paper reported.

In Florida, where another hard-fought governor’s race pits progressive Andrew Gillum against Trump ally Ron DeSantis, more than 2.7 million have already voted in person or by absentee ballot, a record high for a midterm, Politico reported. That means more than a fifth of active voters in the state have already exercised their right.

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Texas has a long record of low turnout – just 28.9% in 2014, second to last among all states. But it has spiked this year, according to the Pew Charitable Trusts.

About 2.4 million people cast ballots in the first days of early voting in the state’s 30 biggest counties – more than the total number of early and absentee votes in the entire voting period in 2014, the United States Elections Project found. In Dallas county, the number is closing in on the number of votes cast in the 2016 presidential election, according to the Dallas Morning News. Presidential contests typically see much higher turnout than midterms.

Texas has traditionally been solidly Republican but the Democratic Senate challenger Beto O’Rourke is giving Republican Ted Cruz a run for his money this year.

In all, 22 million votes have been cast around the US so far, said Michael McDonald, a political science professor at the University of Florida who runs the United States Elections Project. In 11 states, there are more early votes already recorded with a week left to election day than early votes recorded in total in 2014.

“We’re certainly on pace to have a very high turnout,” McDonald said.

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If trends continue, turnout could beat the 49% recorded in 1966, a number that has not been surpassed since in a midterm. Even if voting rates taper off, turnout is still likely to be well above the average of 40% over the last three decades.

“As each day goes by, I have higher confidence we’re going to see the high turnout scenario,” McDonald said.

Early voting numbers have also spiked in Maryland, Montana, Arkansas and Tennessee.

Among voters under 30, 40% said they would “definitely” vote in the midterms, according to a poll by the Harvard Kennedy School’s Institute of Politics. That was up from 27% in 2010 and 26% in 2014.

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It is impossible to say with certainty who will be helped by an increased turnout. Democrats are banking on a “blue wave” driving voters to the polls. A high turnout probably means more young people, people of color and low-income people will vote, McDonald said.

But Republican-affiliated voters outpaced Democrats in early voting in seven of eight closely watched states as of last week, according to data analyzed by NBC News. Republicans have a lead in ballots cast in Florida, according to Politico, though it is smaller than the lead they had in 2014.

It is only possible to track votes at this point by party affiliation – not who the person actually voted for. And the totals do not account for voters unaffiliated with any party.

Election forecasts currently show the Democrats likely to win the House of Representatives but Republicans likely to keep the Senate. Republicans are forecast to be governors in a narrow majority of states.