Control of Congress still hangs in the balance as of Wednesday afternoon, as some competitive House contests remain uncalled and three Senate races are outstanding.

The big picture: Republicans are leading the race for control of the House, but a number of toss-ups are still up for grabs. The razor-thin battle for control of the Senate has winnowed to three key races — Arizona, Georgia and Nevada.

Georgia's high-profile contest between Republican Herschel Walker and incumbent Democratic Sen. Raphael Warnock is heading to a runoff, which will take place on Dec. 6, Republican Secretary of  State Brad Raffensperger announced Wednesday afternoon.

Unless one party wins the remaining contests in Arizona and Nevada, where large numbers of votes are still being counted, control of the chamber will not become clear for another month.

Among the pivotal victories on Tuesday night, Democrats flipped a Senate seat in Pennsylvania, where Lt. Gov. John Fetterman defeated Republican Mehmet Oz.