Rick Santorum, who bowed out of the Republican nominating contest after capturing 11 states and some 3 million votes, endorsed Mitt Romney late Monday.

In a letter to his supporters, the former Pennsylvania senator said that he was impressed with Romney’s “commitment to economic policies that preserve and strengthen families.”



View Photo Gallery: With the Republican presidential nomination essentially assured, former Massachusetts governor Mitt Romney steps up his criticism of President Obama.

“He clearly understands that having pro-family initiatives are not only the morally and economically right thing to do, but that the family is the basic building block of our society and must be preserved,” Santorum wrote in the letter e-mailed to supporters.

The endorsement comes as Romney looks to shore up his support among conservatives, who powered Santorum to victory in several states, particularly in the south.

Last week, Romney and Santorum met for an hour in Pittsburgh, where Santorum stressed the need for Romney to hire conservatives. During the primary, Santorum was one of Romney’s harshest critics, suggesting that he was unelectable because of his health care plan and because of his more moderate views.

Yet Santorum, who resurrected his career with his unlikely challenge of Romney down the stretch, said that he was satisfied that Romney would overturn health care.

“My conversation with Governor Romney was very productive, but I intend to keep lines of communication open with him and his campaign,” Santorum wrote. “ I hope to ensure that the values that made America that shining city on the hill are illuminated brightly by our party and our candidates thus ensuring not just a victory, but a mandate for conservative governance.”

Santorum dropped out of the race weeks before the Pennsylvania primary with millions of dollars in campaign debt.

With Santorum’s endorsement, Romney has landed the backing of all but two of his challengers, Newt Gingrich and Ron Paul who still remains in the race.

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