Americans are casting ballots ahead of Election Day at a pace never seen in a midterm year. More than 51 million people had already voted by Saturday as the campaign rolled into its final weekend, topping the nearly 46 million early ballots counted before Election Day four years ago.

The total covers both mail ballots and in-person early votes. It was compiled by researchers at the University of Florida who track returns from election offices across the country. With three days still to go, the number is likely to keep climbing through Monday.

Ohio is one of the clearest examples. By early Saturday morning the state had logged 1,485,900 early votes, edging past its old midterm mark of 1,473,983 set in 2022. Officials there expect lines to stay busy through the last day of early voting.

Why the stakes feel so high

Control of Congress is on the line. Republicans hold the Senate 53-47, so Democrats need a net gain of four seats to take over. Thirty-five Senate seats are on the ballot this year along with all 435 seats in the House.

A handful of close Senate contests in states such as Michigan, Maine, Ohio, Texas, North Carolina and Alaska have drawn heavy spending from both parties. Strategists on each side say the early numbers show deep interest but warn that it is too soon to tell which party the surge will help.

Early voting habits have shifted since the pandemic. Many voters who once waited for Election Day now prefer to mail a ballot or stop by an early site when the lines are short. Election officials say spreading turnout over several weeks also eases pressure on polling places on the big day.

Last-minute storylines

In Alaska, a federal grand jury inquiry is looking at Democrats over a second candidate on the Senate ballot who shares a last name with Republican Sen. Dan Sullivan. Voters outside early sites in Anchorage on Saturday said the ballot was clear to them and that the fuss did not change their plans.

In Michigan, Democratic Senate nominee Abdul El-Sayed is closing out his race under fresh scrutiny. His campaign asked former primary rival Rep. Haley Stevens to skip its remaining events after she demanded he condemn an outside group's ad, a sign of lingering tension inside the party in a state both sides view as crucial.

Campaigns are now shifting money and volunteers toward getting their last supporters to the polls. Polls close Tuesday night, though counting in some states can take days because of mail ballots that arrive close to the deadline.

Election Day is Tuesday, Nov. 3.