Rubio endorses Romney, says GOP primary should end

Republican Sen. Marco Rubio of Florida endorsed Mitt Romney as the party's presidential nominee Wednesday night, saying it's increasingly clear that Romney will win the nomination and that continuing the primary fight will only damage the effort to defeat President Barack Obama.

Rubio, a freshman senator and tea party favorite, said he's convinced that Romney will govern as a conservative and will be superior to Obama as a president.

"The quicker we can get this campaign on that focus — focused on the president's record, on the alternative that we offer — the better off we're going to be as a movement but also the better off the country's going to be," Rubio said during an interview with Fox News Channel.

Rubio had pledged to stay neutral in the race. But on Wednesday he said a floor fight over the nomination at the party convention in August would be "a recipe to deliver four more years to Barack Obama."

Rubio's endorsement followed that of former Florida Gov. Jeb Bush and came a day before former President George H.W. Bush was to back Romney — additional signs that more and more party leaders are falling in line behind Romney rather than Rick Santorum, Newt Gingrich or Ron Paul. Gingrich has scaled back his campaign, saying he wants to focus on winning the nomination at the convention if Romney fails to win enough delegates during the primary race.

Rubio has been mentioned as a potential running mate on the GOP ticket. He told Fox News that his heart, mind and focus remain on the Senate and said he doubts he would be asked to join a Romney ticket.