Mitt Romney
President Obama's campaign team is going after Mitt Romney. Reuters

Former Republican presidential candidate Tim Pawlenty endorsed Mitt Romney for president on Monday, further sharpening the distinction between Romney and Texas governor Rick Perry.

Pawlenty used the endorsement, which he issued on the program Fox and Friends, both to praise Romney and to criticize Perry's inflammatory comments on Social Security, which Perry likened to a Ponzi scheme.

I believe he's going to be our party's nominee, Pawlenty said of Romney, adding that he believed Romney would be a transformational and great president who boasted great success when it comes to growing jobs and the economy.

Romney has been attacked by rival candidated for overseeing Massachusetts adopting universal healthcare when he was governor, a move that his opponents have used to tie him to President Barack Obama's healthcare overhaul. Pawlenty dismissed those concerns, saying conversations with Romney had convinced him that Mitt Romney is 100 percent dedicated and committed to repealing Obamacare.

Pawlenty also thrust himself into the intensifying clash between Perry and Romney, implying that Perry's views on Social Security made him too extreme to be electable.

Gov. Romney wants to fix Social Security. He doesn't want to abolish it or end it, Pawlenty said. Gov. Perry has said in the past that he thought it was 'failed.'