DURHAM, N.C. -- In his first public appearance since Mitt Romney unveiled Paul Ryan as his running mate, Vice President Joe Biden lashed the new GOP ticket to the Bush administration and said that Ryan's budget makes the differences between Obama and his Republican rivals even more stark.

"Congressman Ryan has given definition to the vague commitments that Romney's been making," Biden said of Ryan's controversial budget proposition during a Monday speech at the Durham Armory.

Calling his Republican counterpart a "good guy," Biden took issue with those who call the Ryan budget, which would fundamentally overhaul entitlement programs, a "gutsy" proposition.

"What's gutsy about giving millionaires another tax break? "What's gutsy about gutting Medicare, Medicaid, education?" Biden asked. "They talked about what they're proposing as new. Folks, this is only not new, it's not fair."

Met by cheers from the audience of several hundred, the vice president predicted that the American people will reject the Romney-Ryan effort "to impose on the American people what the Republican congress has been preaching."

Biden, on the first stop of a three-day swing through battleground states North Carolina and Virginia, argued that Ryan's voting record served as yet another GOP rubber stamp for decisions that led to the 2008 financial crisis.

"How do they think we got in this mess in the first place?" he asked. "As my little granddaughter would say, was it Casper the ghost who came along and did this? Who did it?"

The remarks tee up a new role for the vice president as one of the Obama campaign's strongest counterweights to Ryan's plan to overhaul entitlements, a measure that Democrats hope will be devastatingly unpopular for the GOP ticket in retiree-heavy states like Arizona and Florida.

Twenty-seven years separate Biden, who is known to enjoy watergun fights with his bevy of grandkids, and Ryan, a father of three children still years shy of their learners' permits.

Biden, one of the youngest senators in U.S. history, joined the ranks of Congress just weeks before Ryan's third birthday.

The vice president drew one biographical similarity between himself and the young congressman -- noting that both commonly quote their fathers.

"I'm glad to see that Congressman Ryan likes his dad too, quotes his dad." Biden noted. "I mean that sincerely."

Ryan's father died of cancer when he was a teenager.

Biden's trip also served as an organizing tool for Obama staff in North Carolina. Supporters who volunteer three times for a total of nine hours will receive a guaranteed credential for the president's convention speech, organizers announced at the start of the event.