Jeffrey Phelps/AP Photo

Mitt Romney may have his own budget plan, but as far as Medicare is concerned, he and Paul Ryan are almost of one mind.

"I have my budget plan," Romney said Sunday in North Carolina. "And that's the budget we're going to run on."

Paul Ryan's 2013 budget plan, passed by the House in March, includes a lot of things, and Mitt Romney has endorsed it in the past, telling Wisconsin supporters in a tele-town-hall meeting four days after the House passed it.

"I think it'd be marvelous if the Senate were to pick up Paul Ryan's budget and to adopt it and pass it along to the president," Romney said.

On the topic of Medicare specifically, Romney backs the same outline Ryan drafted in conjunction with Democratic Oregon Sen. Ron Wyden in December. In fact, Romney's website implies the presumptive GOP nominee came up with it first.

Where Romney's website lays out his Medicare plan, it enumerates the broad strokes of Ryan's latest iteration: an overhaul that would give seniors the options of 1) entering a voucher/subsidy program and buying government-approved private insurance programs, with "premium-support" checks to help with the payment, or 2) enrolling in Medicare's own coverage plan, like the program works today.

Romney's site states that Ryan's plan "almost precisely mirrors" Romney's:

How is this different from the Ryan Plan? Shortly after Mitt presented the proposal described here, Congressman Paul Ryan and Senator Ron Wyden introduced a bipartisan proposal that almost precisely mirrors Mitt's ideas. Unsurprisingly, the Obama administration immediately rejected the proposal. Mitt has applauded the Ryan-Wyden effort and looks forward to working as president with leaders from both sides of the aisle to implement meaningful reforms that will preserve Medicare for future generations.

Romney has defended Ryan's plan since naming him as the GOP's vice presidential candidate, and when the House passed Ryan's budget in March, Romney issued this statement praising it:

We are making progress. The House of Representatives has unanimously rejected President Obama's vision of an America with higher taxes, unlimited spending, and expansive government. Owing in no small part to the leadership of Paul Ryan, it has put conservative fiscal principles into action and passed a bold budget that directly addresses the drivers of our nation's spending crisis. The House budget and my own plan share the same path forward: pro-growth tax cuts, getting federal spending under control, and strengthening entitlement programs for future generations. I look forward to working with Congress to achieve fiscal discipline and passing a budget that moves us toward a simpler, smarter, and smaller federal government.

Ryan endorsed Romney the next day.

In Florida today, ABC's Emily Friedman reports that Romney was asked, by a gaggle of reporters, how his budget differs from Ryan's. He provided no specifics on the spot.

"I'm sure there are places that my budget is different than his but we're on the same page as I've said before, we want to get America on track to a balanced budget," Romney said. Pressed again by another reporter on differences in their ideal budgets, Romney said, "There may be, we'll take a look at the differences."

But Romney has not endorsed the "Ryan Plan" of yesteryear-the drastically more conservative Medicare proposal for which Ryan became known.

Ryan's latest Medicare plan is different from his previous model in several major ways. In December, he released a new version along with Wyden, ranked by National Journal as the Senate's 17th most liberal member.

That plan entailed significant differences from the version Ryan proposed from 2008-2011-the version that became welded to Ryan's political identity as he defended it relentlessly against Democratic criticism. Support for that plan became a litmus test for GOP candidates'Tea Party credentials, and, after some Republicans resisted it, Ryan's 2011 Medicare reforms became GOP orthodoxy.

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In the old version, seniors would not have the public option Ryan/Wyden affords them. For those under 55, Medicare would cease to function as a fee-for-service health-coverage provider; instead, it would become a voucher-esque program in full. Medicare would become a board that approves private insurance plans and doles out "premium-support" payments to seniors, subsidizing their purchases of those plans. In 2011, critics feared that Ryan's premium-support payments would not grow fast enough, leaving seniors unable to afford coverage or out-of-pocket expenses for care.

Ryan overhauled his overhaul along with Wyden, making drastic changes that addressed most of those fears. Under his latest, almost unrecognizable 2012 proposal, seniors could opt into Medicare as-is, a fee-for-service provider that pays hospitals for a set of benefits. For those who choose subsidized private insurance, payments would be indexed not just to inflation (as in Ryan's previous version), but to the cost of insurance plans. A catastrophic-care benefit would limit out-of-pocket costs.

So if you overhear a debate over whether "Mitt Romney supports the Ryan Plan," keep in mind that "the Ryan Plan" could mean many things: his overall budget, the 2011 Medicare-reform plan that would end the program as we know it and for which Ryan became known, or the drastically different 2012 version crafted with a Democrat and potentially carrying centrist appeal.

Romney supports that last one, but the specifics can easily be lost in the debate.

Emily Friedman contributed to this post.