(CNN) - Early voting gets underway in Alaska, Arkansas, Colorado, Florida, North Dakota, Texas, and the District of Columbia Monday.
That brings to 27 states plus the District of Columbia where early or state-wide absentee voting is underway in the November 2 midterm elections.
Vermont kicked it off back on Sept. 20. Other states were early voting or state-wide absentee voting is under are Georgia, Maine, South Dakota, Iowa, Wyoming, Nebraska, Ohio, Wisconsin, California, Indiana, Montana, Arizona, Illinois, Idaho, Kansas, Tennessee, West Virginia, North Carolina, New Mexico, and Nevada.
Hawaii, Louisiana and Utah allow early voting as of Tuesday, with Oklahoma kicking in on Oct. 29.
In 2008, there were 27 states where at least a quarter of the voters cast their ballots before Election Day, either through absentee voting or early voting. And there were 11 states where more than half of voters cast their ballots before election day.
As early voting has exploded over the past few election cycles, it's changed the game for both voters and campaign strategists.
"Early voting has grown in popularity, with more voters in more states casting ballots before Election Day. It's really changed the decision calculus behind elections for both candidates and voters. It can be a double-edged sword," says CNN Political Research Director Robert Yoon.
"For the campaigns, if someone casts an early ballot for you, it's like money in the bank. But if they vote against you, that's a lost vote that no amount of TV ads or baby-kissing can change. For voters, you just have to hope that the candidate you voted for back in September is still the candidate you want on November 2nd," adds Yoon.
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