Sen. Kyrsten Sinema, a former Democrat-turned-independent who has long been a bogeyman for liberals, is retiring this year, and Democratic Rep. Rueben Gallego is facing Republican Kari Lake in a race for the open seat. Gallego, who represents Phoenix and the surrounding western suburbs in Congress, has a fundraising advantage, having raised nearly $22 million through the end of September, while Lake has raised nearly $17 million.

Lake, a polarizing Trump ally, first ran for governor in 2022 and refused to accept the election results. A CBS News poll conducted from October 11 to 16, Gallego had a 9-point lead over Lake.

A CBS News poll conducted from October 11 to 16 in Arizona, Trump had a 3-point lead against Harris. Trump is boosted by voters who say immigration/border and the economy are their top issues, while Harris has advantages among voters who prioritize abortion rights and the state of democracy, which keeps this race close.

Polls in Arizona close at 7:00 PM MT (9:00 PM ET).