Florida Democratic Rep.
For several weeks Murphy, who has served in the House since being elected in 2012, has hinted he might run in the race and has been a top recruit of the Democratic Senatorial Campaign Committee.
His entrance comes as incumbent Republican Sen.
Last week, Rep.
In his campaign announcement, Murphy attacked Rubio, saying Florida's junior senator has "put his presidential ambitions before the needs of the people of this state."
"We need a leader in the Senate whose eyes are firmly fixed on the people of Florida by working together to get things done," Murphy said. "In the coming months, I look forward to meeting Floridians across the state to listen, earn their trust and ask for their support."
Republicans who might look to succeed Rubio should he run for president include the state's Chief Financial Officer
Florida, a swing state in presidential elections, is also home to former Gov. Jeb Bush, who is widely expected to run for president along with Rubio.