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Paul Ryan came out swinging Saturday in his new role as Mitt Romney's running mate, accusing President Obama of presiding over a "record of failure" and promising to speak "truth" to America's problems and correct course.

"We can turn this thing around," Ryan vowed, as he and Romney joined for the first time as the official 2012 Republican ticket.

The Wisconsin congressman, to the backdrop of retired battleship USS Wisconsin, gave a feisty opening speech -- setting the tone for the Romney-Ryan bus tour that's next on the agenda, and the race going forward. Dutifully promoting the top of the ticket, Ryan touted Romney as the solution to the economic problems under Obama.

Met with chants of "USA, USA" from a riled-up crowd in Virginia, Ryan spoke broadly about the virtues of free enterprise and specifically about America's economic woes, all laced with pointed attacks on the White House incumbent. Though Ryan's reputation is that of a reserved and wonkish pol, his break-out speech as running mate signaled he'll be playing offense for Romney quite frequently.

Ryan accused the Obama team of being "more worried about their next election than they are about the next generation." He blamed Obama's "misguided policies" for the economic rut the country's been stuck in.

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"No one disputes that President Obama inherited a difficult situation. And, in his first two years, with his party in complete control of Washington, he passed nearly every item on his agenda. But that didn't make things better," Ryan said. "In fact, we find ourselves in a nation facing debt, doubt and despair. ...

"Whatever the explanations, whatever the excuses, this is a record of failure."

Ryan may continue pushing for a version of the budget proposal he reintroduced earlier this year. That proposal would overhaul Medicare and Medicaid and make other sweeping changes that Democrats have labeled as extreme. But Ryan has stuck by his proposal as the solution to an ever-growing deficit inflamed by out-of-control entitlement spending.

In a dose of the tough-love approach Ryan's become known for, he said: "We promise equal opportunity, not equal outcomes."

The Republican presidential candidate called his new running mate a man of "steadiness" and "integrity" as he introduced him. Speaking Saturday morning, Romney praised Ryan as an "intellectual leader" of the party, one who understands the toll the debt is taking on the country but is optimistic about the future.

"He doesn't demonize his opponents. He understands that honorable people can have honest differences and he appeals to the better angels of our nature," Romney said. "He's never been content to just curse the darkness. He'd rather light candles."

Romney initially fumbled his introduction of Ryan. In the closing line of his remarks, he referred to Ryan as the "next president." Romney quickly returned to the podium to correct himself.

The selection comes roughly two weeks before the start of the Republican National Convention in Tampa, and gives Romney plenty of space to rally the party behind his pick before the official nomination.

The announcement comes as some polls, including a recent Fox News survey, show the Republican presidential candidate losing some ground to President Obama.

Ryan, 42, already considered a rising star in the Republican Party, is chairman of the House Budget Committee. He's been in Congress since 1999 and is best known this session for his controversial budget plan that includes an overhaul of Medicare.

Democrats have persistently tried to vilify that plan as a scheme to "end Medicare as we know it."

The Obama campaign repeated that line in its first official response to the Ryan selection Saturday morning.

"The architect of the radical Republican House budget, Ryan, like Romney, proposed an additional $250,000 tax cut for millionaires, and deep cuts in education from Head Start to college aid. His plan also would end Medicare as we know it by turning it into a voucher system, shifting thousands of dollars in health care costs to seniors," the campaign said. "As a member of Congress, Ryan rubber-stamped the reckless Bush economic policies that exploded our deficit and crashed our economy. Now the Romney-Ryan ticket would take us back by repeating the same, catastrophic mistakes."