For a moment, at least, presidential campaigns get back to issues

On the Sunday TV talk shows, presidential campaign surrogates of both parties zeroed in on Medicare. But inevitably, Mitt Romney's so-far unreleased tax returns came up too.

First comes a handful of mud slung at an opponent. Then a bucketful. Pretty soon everybody’s doing it, nobody left unmuddied or with clean hands.

So it goes in campaign politicking, where the only thing worse than too much mud (or too much PAC money) is what both Mitt Romney and Barack Obama have referred to as “unilateral disarmament.”

Maybe because it was the Christian Sabbath – both Obama and Romney went to church with their families – or maybe it was the summer weather. But things seemed to calm down a bit Sunday when campaign surrogates faced off on the TV talk shows – talking mainly about the issues.

On ABC's "This Week," Sen. Pat Toomey (R) of Pennsylvania and Rep. Chris Van Hollen (D) of Maryland – both budget committee members – debated Medicare.

"What [the Romney-Ryan] plan does it says we're going to have competition, starting ten years from now, mind you, anybody who's currently getting Medicare gets exactly what they're getting now and that doesn't change,” said Sen. Toomey. “But what happens is for someone such as myself, who's 50, when I reach retirement age, I'm going to have a range of choices.”

“The government isn't going to have a specified dollar amount, it's going to require insurers to compete,” he continued. “It will set that dollar amount based on that competition, insuring that I will always be able to receive from the government a premium necessary to buy a plan that's equivalent to current Medicare.”

“Equivalent to current Medicare?” Not so, argued Rep. Holland.

"The Romney/Ryan plan would immediately increase costs for seniors," Rep. Holland said. "By design, it saves Medicare money by providing seniors with a voucher that declines in value relative to rising health care costs. So health care costs are going up, the value of the voucher does not keep pace. Seniors will have to eat that cost, as opposed to the president's Medicare plan, which says we need to contain costs by changing the incentives in the health care system to reward providers for the quality of care they provide, rather than the quantity of care."

It’s unlikely that their exchange changed many voters’ minds or even clarified the complications of Medicare very much.

On "Fox News Sunday," Republican adviser Ed Gillespie was asked about a nonpartisan Congressional Budget Office finding that under Romney's "premium support" proposals, "Medicare beneficiaries will bear a much larger share of their health care cost."

"We reject that in our analysis," Gillespie said. He said Romney's overall plans, including a higher eligibility age, eventually would slow the program's growth.

"There was going to be a battle about Medicare, no matter what,” Republican political consultant and policy advisor Karl Rove said on “Fox News Sunday.”

“The question was: Was it going to be left to what the Democrats traditionally do – which is late-night phone calls in the final week of the campaigns, to seniors, and scary mail pieces?” said Rove. Or were we going to have a full-out, honest debate? And we're having, for what passes in politics, a full-out, honest debate about it."

Romney’s personal finances – including his so-far unreleased tax returns – remain an issue, not only for Democrats but for some prominent Republicans and conservative pundits who have urged him to be more forthcoming.

"Look, Mitt Romney is a highly educated man. And he has clearly made a decision that what is in those tax returns is far more damaging to him than to do what every presidential candidate has done, which is show the American people your personal finances," Obama campaign senior adviser Robert Gibbs told "Fox News Sunday."

“We know that he has been engaged in tax-avoidance schemes with offshore accounts in the Cayman Islands and the Bahamas,” Maryland Governor Martin O'Malley (D) said on NBC's "Meet the Press.” “It’s not unlawful, but it is tax avoidance.

Romney surrogates did their best to change the subject.

“This isn’t what the American people care about,” retorted Virginia Gov. Robert McDonnell (R) “This is below their dignity. This is about how do we get the greatest country on earth out of debt and back to work. And Obama just flat failed. Nice guy, bad policies. Hasn’t gotten the job done.”

Romney adviser Eric Fehrnstrom insisted Sunday on CNN’s “State of the Union” that “taxes are not an issue.”

"Mitt Romney has said he'll put out two years of tax returns,” he said. “He put out his 2010 return, hundreds of pages of tax return information that’s on the website. He’ll put out his 2011 returns once it's complete and filed.”

But  that’s unlikely to satisfy most people as Democratic operatives continue to needle Romney on the apparent secrecy involving his personal finances. A CNN/ORC poll published this month showed 61 percent of registered voters believe Romney should release more than two years of tax returns.