Mitt Romney officially announced Monday afternoon with a tweet and video posting that he will form an exploratory committee to seek the presidency in 2012 -- a widely expected development -- citing his private sector experience and the need to reinvigorate the economy.

"Today, I am announcing my exploratory committee for the presidency of the United States," the former governor of Massachusetts said. "It's time that we put America back on a course of greatness with a growing economy, good jobs, and fiscal discipline in Washington."

Romney enjoys strong name recognition and leads the GOP field in several national surveys and straw polls. But he's dogged by his evolving views on a plethora of issues and his support for a state health care reform measure -- enacted five years ago today -- that bears a striking resemblance to the sweeping law President Barack Obama signed last year.

Watch the video announcement, via

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