Kristen Carlson of Lakeland endorses fellow Democrat Adam Hattersley in his challenge to U.S. Rep. Ross Spano. Carlson lost to Spano in the 2018 election.

LAKELAND — Kristen Carlson, the Democratic nominee in 2018 for the U.S. House District 15 seat, has endorsed fellow Democrat Adam Hattersley in his challenge to incumbent U.S. Rep. Ross Spano, R-Dover.

Carlson, a Lakeland resident, told The Ledger earlier this year that she hadn't yet decided on a possible run again for the seat. District 15 covers Lakeland and northern Polk County, as well as parts of Hillsborough and Lake counties. The endorsement signals that she won't seek a rematch with Spano.

Spano defeated Carlson by 6 percentage points in the 2018 election. Questions about Spano's campaign finances emerged when federal filings revealed he received about $180,000 from two friends — then loaned a similar amount to his campaign.

That appeared to be a violation of Federal Election Commission rules that limit individual contributions to $2,700 per election cycle. Spano's lawyer wrote to the FEC saying the campaign might have inadvertently violated campaign rules.

Carlson asked the FBI to investigate Spano's campaign over the loans. Jan Barrow, president of the Democratic Women's Club of Lakeland, also has asked the FEC to investigate Spano.

“The people of this district were robbed last year when Ross Spano funneled illegal money into his campaign and stole a seat in Congress,” Carlson said in a statement. “I am thrilled to be supporting Adam's campaign because I know firsthand what it takes to run for Congress. ... Adam embodies everything an elected official should be and I look forward to working with him to win in November.”

Hattersley, a Riverview resident, won election to a first term in the Florida House in 2018. He entered the race against Spano two weeks ago, prompting fellow Democrat Andrew Learned to drop from the race and run for Hattersley's seat in the Legislature.

Hattersley is a Navy veteran who co-owns a print marketing business with his wife, Christie. The Democratic Congressional Campaign Committee has set the District 15 seat as one of its primary national targets for 2020.

Gary White can be reached at gary.white@theledger.com or 863-802-7518. Follow on Twitter @garywhite13.