Mitt Romney on Saturday announced U.S. Rep. Paul Ryan of Wisconsin as his running mate for the White House -- a bold and risky move that energized both conservatives and their opponents.

Ryan is a rising Republican star and the party's leader on fiscal and budget issues.

He is the architect of a Republican spending plan that would overhaul many entitlement programs, making him a favorite of conservatives, whose support for Romney, the presumptive Republican presidential nominee, has been shaky.

But the Romney camp was also quick to put some distance between Ryan's initial budget blueprint and his own.

"Gov. Romney applauds Paul Ryan for going in the right direction with his budget," the campaign said, "and as president he will be putting together his own plan for cutting the deficit and putting the budget on a path to balance."


His running mate choice draws some clear lines with Romney's Democratic opponents over the size of the cuts in Ryan's plan and his prior votes on taxes, which they say favor the wealthiest Americans -- a point of contention in an election in which both sides consider themselves champions of the middle class.

"Congressman Paul Ryan is an outstanding choice as our country's next vice president, and today's announcement demonstrates Governor Romney's commitment to returning fiscal sanity back to Washington, DC.," said former Pennsylvania Sen. Rick Santorum, who mounted the strongest conservative challenge to Romney's campaign in the Republican primaries.

"I have long supported Paul Ryan's fiscal and entitlement reforms to return our country back on a path of fiscal health."

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