In the House battle, Florida's toss-up 26th District has drawn an influx of recent cash. Republican Rep. Carlos Curbelo, who has cast himself as a centrist, is trying to defend a South Florida district that Hillary Clinton won in 2016 amid a challenge from Democrat Debbie Mucarsel-Powell. She outraised the GOP representative by more than $100,000 from Oct. 1 to Oct. 17, although Curbelo has taken in about $1 million more throughout the campaign.

In another toss-up, the 15th District, Democrat Kristen Carlson took in about $400,000 from Oct. 1 to Oct. 17, compared with roughly $150,000 for Republican Ross Spano. They are vying to succeed retiring Republican Rep. Dennis Ross in the district east of Tampa.

The competitive Miami-area 27th District race has also seen a stream of cash in the midterms' final days as the parties push to succeed retiring GOP Rep. Ileana Ros-Lehtinen. Democrats saw the district, which Clinton won by more than 20 percentage points, as one of their best pickup opportunities.

But Democratic former Health and Human Services Secretary Donna Shalala has faced challenges in the district against the Republican candidate, popular Cuban-American former news anchor Maria Elvira Salazar.

Shalala's campaign took in more than $700,000 from Oct. 1 to Oct. 17, versus about $350,000 for Salazar's campaign.

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