The battle for control of the U.S. Congress hangs in the balance two days after the midterm elections, when predictions of a “red wave” of Republican victories failed to materialize. Three undetermined races will determine whether Democrats or Republicans hold power in the Senate.

In Arizona, incumbent Democratic Senator Mark Kelly has a significant lead over Republican Blake Masters, with nearly a third of ballots yet to be counted.

In Nevada, Trump-supporting Republican Adam Laxalt is leading incumbent Democratic Senator Catherine Cortez Masto by fewer than 20,000 votes. Most of the 20% of the ballots yet to be counted are mail-in votes from urban areas likely to favor Cortez Masto.

In Georgia, newly reelected Republican Secretary of State Brad Raffensperger announced plans for a December 6 runoff in Georgia’s Senate race. Incumbent Senator Raphael Warnock received about 30,000 more votes than his Republican rival, former NFL star Herschel Walker. But Warnock fell just shy of the 50% mark needed to avoid a runoff.

In Wisconsin, Democratic Lieutenant Governor Mandela Barnes has conceded to incumbent Senator Ron Johnson in a closely fought contest. Senator Johnson is a climate denier who has downplayed the January 6 Capitol riot; just ahead of the insurrection, Johnson and his staff tried to deliver lists of fake electors to Vice President Mike Pence.