A new Obama campaign TV ad airing today in eight swing states invokes the powerful AARP in response to Republican attacks on the president's Medicare plan.

The 30-second spot, dubbed "Facts," is the first from Obama this campaign that addresses Medicare, citing AARP's support for $716 billion in Medicare spending cuts imposed by the health care law that are now a focal point of debate.

"And the Ryan plan?" the narrator says. "AARP says it would undermine Medicare and could lead to higher costs for seniors. And experts say Ryan's voucher plan could raise future retirees costs more than $6,000."

AARP says it has 40 million members.

Presumptive GOP nominee Mitt Romney and running-mate Rep. Paul Ryan have argued that Obama has undermined Medicare by reducing payments to providers and not addressing the program's long-term financial sustainability. They propose restoring the Obama cuts and eventually transitioning the program to a fixed benefit, voucher-style system that they say would reduce costs.

"President Obama's new ad, 'Facts,' gets the facts wrong," Romney spokeswoman Amanda Henneberg said. "The facts concerning the president's record on Medicare are clear: 1) Obama cut the program by $716 billion, 2) millions will be forced to lose their Medicare Advantage coverage and 3) the program will go bankrupt in 2024."

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Obama campaign aides believe that the backing and brand-name influence of the nation's largest - and nonpartisan - advocacy group for seniors will effectively neutralize the GOP claims.

Henneberg did not immediately respond to questions about AARP's assessment of the competing approaches to Medicare or whether the group's reputation among seniors would make the Romney-Ryan argument more difficult.

The new Obama ad will air in New Hampshire, Virginia, North Carolina, Florida, Ohio, Iowa, Colorado and Nevada, the campaign said.

UPDATE: In a statement on the ad, AARP distances itself from the Obama campaign, insisting the group had no involvement in the ad and has not endorsed Obama. AARP senior vice president John Hishta exhorts both candidates to engage in "straight talk, not just 30-second ads" when it comes to debating the future of Medicare.

He does not, however, disavow the group's critical past assessments of the Ryan Budget or praise for "Obamacare," both mentioned in the ad.