ATLANTA (AP) — Campaigns and outside groups are making a final push to turn out election-weary Georgians whose votes will determine control of the U.S. Senate, from a crush of text messages and television ads to dueling visits from President-elect Joe Biden and outgoing President Donald Trump. 

More than 2.5 million people — about half the turnout of last month's presidential election — had already cast their ballots early, in person or by absentee ballot, by Wednesday morning. 

With margins in the Jan. 5 runoffs expected to be tight, the campaigns for Republican U.S. Sens. David Perdue and Kelly Loeffler and Democratic challengers Jon Ossoff and Raphael Warnock are all focused on mobilizing voters.

That means everything from individual voter contacts urging early voting, which ends Thursday, to last-minute campaign stops from national headliners trying to boost Election Day turnout. The Democrats' campaigns announced Wednesday that Biden would campaign Monday in Atlanta with Ossoff and Warnock. Trump already had announced plans to rally Monday evening, just hours before polls open, with the Republican senators in the north Georgia town of Dalton. Vice President-elect Kamala Harris, meanwhile, will come to Savannah on Sunday. 

"We want to run through the tape. We don't want to leave anything for granted," said Jessica Anderson, executive director of Heritage Action, a grassroots conservative organization that has volunteers and staffers knocking on doors, making phone calls and sending text messages.

Roshan Mody is the co-founder of Plus1Vote, which focuses on getting young people out to vote on climate change, social justice and voting rights. He told progressive activists Monday during an online briefing that it's going to come down to turnout. 

"All the signs are good," he said of Democrats' chances. "But a blowout is less likely than us kind of going over the edge by 10-20,000 votes."