Florida Rep. David Jolly is running for re-election in the 13th District.
"Today I'm asking you for the opportunity to keep doing my job," Jolly wrote in an email to supporters Friday afternoon. "I ask for your support in seeking reelection to the House of Representatives."
Jolly had been seeking the GOP nomination for Senate along with four other candidates.
Jolly's departure from the Senate race comes amid speculation that Florida Sen. Marco Rubio will file for re-election on Monday.
Jolly said on CNN Friday morning that Rubio is "saying he is getting in," but later walked back that statement. Rubio has said he plans to spend the weekend considering his options.
Jolly has said he is the only Republican who can win in his district, which became more Democratic in recent redistricting. Former Florida governor Charlie Crist is running on the Democratic ticket.
The Rothenberg & Gonzales Political Report/Roll Call rated the 13th District Safe for Democrats before Jolly's decision. The rating is unlikely to change until the congressman proves he can defeat Crist in the redrawn district.