A vote for Mitt Romney is a vote for the Medicare cuts championed by his running mate, Rep. Paul RyanPaul Davis RyanGOP leaders pitch children's health funding in plan to avert shutdown Lawmakers see shutdown’s odds rising Fix what we’ve got and make Medicare right this year MORE (R-Wis.), Vice President Joe BidenJoseph (Joe) Robinette BidenDemocrats will need to explain if they shut government down over illegal immigration Trump thinks he could easily beat Sanders in 2020 match-up: report Biden marks MLK Day: Americans are 'living through a battle for the soul of this nation' MORE warned voters in Florida this weekend.

Although Romney, the GOP presidential nominee, has sought to distance himself from Ryan's budget – including the sharp cuts to Medicare – Biden said Saturday that the Budget Chairman's proposal is the best indication what a President Romney would endorse from the White House.

Rallying the Democratic faithful in Fort Myers, Fla., Biden characterized Ryan as "the ideological center" of the Republican Party and warned the crowd that Romney's plan to cut Medicare – among other popular federal programs – is hiding in plain sight.

"What Gov. Romney did in picking Paul Ryan is he has given clear definition to all those vague assertions he was making during his primary campaign," Biden said. "[And] nowhere is it more clear what they would do than in Medicare."

Romney has taken heat for being vague about his plans to tackle a number of prominent issues, including Medicare and tax reform. He's vowed to repeal Obama's healthcare reform law, for instance, but he hasn't specified what he'd replace it with. And while he's said he'll offset his across-the-board income tax cut proposal by eliminating tax benefits elsewhere in the federal code, he hasn't named which loopholes he'd close.

Biden on Saturday suggested Ryan's budget fills in the blanks.

"So now we don't have to guess about what Mitt Romney means when he talks about Medicare vaguely and Social Security and education and all these things, because it's almost like two incumbents running," Biden said. "We don't have to wonder any more, 'Exactly what does Gov. Romney mean?'"

The message holds particular significance in Florida, a vital battleground state where a huge proportion of voters are seniors on Medicare. 

Romney's choice of Ryan as running mate was hailed by conservatives as a sign that the former Massachusetts governor has rejected some of the more moderate positions he'd championed in the past and would fight hard for policies favored by the right, particularly on entitlements and federal spending. But it was also a gamble, as Ryan is practically synonymous with his budget proposals, which include steep cuts to Medicare, education and other popular federal programs.

Republicans, who approved Ryan's budgets on the House floor both this year and last, argue that the cuts are necessary to rein in government spending that's grown out of control. Democrats concede that spending needs to fall, but they've rejected cuts that aren't accompanied by some tax hikes, particularly on the highest earners – a notion congressional Republicans have opposed.

The impasse has spurred a months-long debate over the government's role in the economic recovery and which class of Americans are best suited to spur a rebound.

Biden on Saturday said the Republican's spending cuts were designed simply to offset the loss of revenues inherent in their plan to shower new tax benefits on the rich.

"This is all in the service of tax cuts for the super wealthy," he said.

Romney, during the GOP primaries, had endorsed Ryan's budget. More recently, however, he's sought to distance himself from its more controversial elements.

“Congressman Ryan has joined my campaign, and his campaign is my campaign now,” Romney said in August after tapping Ryan as his running mate.

It's an argument Biden was quick to reject Saturday.

"They [Republicans] have no credibility on this issue," he charged.

Biden's speech – ending a two-day sweep through the Sunshine State – came just days ahead of the first presidential debate, as Republicans are hoping to shift the campaign's focus to jobs and the economy, where they think Romney and Ryan have an edge over the Democrats.