Recent polling data shows that the issue resonates with boomers in key swing states. In Wisconsin, about 80 percent of respondents aged 50 to 64 ranked Medicare as "important" or "very important" in a Quinnipiac University/CBS/New York Times survey taken August 15-21, versus 91 percent for those 65 and older. Florida and Ohio produced comparable results in the same survey.

There are 41 million seniors and 61 million boomers in the United States. With numbers like that vitally interested in a single issue, the importance of Medicare is likely to grow as the presidential campaign and congressional races move into the post-Labor Day home stretch.

Vice presidential nominee Paul Ryan made that clear in his acceptance speech Wednesday at the Republican National Convention in Tampa, Florida.

The Wisconsin congressman did not mention his plan to revamp the healthcare program for the elderly, which would affect people 54 and younger but not current seniors. Instead, he launched an attack on President Barack Obama for diverting money from Medicare to the broader healthcare overhaul.

The next night, Mitt Romney stuck to the script, mentioning Medicare only once in an attack on Obama as part of his presidential nomination acceptance speech.

Democrats responded by pounding at the Republican plan that, as they say in their ads, would "end Medicare as we know it."

Medicare moved to the forefront of the campaign three weeks ago after Romney chose Ryan as his running mate. The "Ryan plan," much of which Republicans incorporated into their party's platform at the convention, would replace Medicare's wide-ranging coverage of health services for the elderly with a voucher program for seniors to buy their own care.

Polls consistently show that Republicans have an edge among seniors, whose defense of Medicare has traditionally made it a politically untouchable issue. Obama and his fellow Democrats hope the Ryan plan will shift some of that support their way.

Party strategists believe even richer spoils could be had among baby boomers. That group, which includes large numbers of the independent middle-class voters Obama needs for re-election, tends to favor Democrats.

"Baby boomers are particularly concerned about the stability of their retirement," said U.S. Representative Steve Israel of New York, chairman of the Democratic Congressional Campaign Committee.

"If you're a baby boomer in the middle class, since 2000 you've seen the value of your paycheck decline, the value of your home decline and you've seen your 401(k) diminish and you're worried about your retirement," Israel said. "What's the Romney-Ryan solution? End Medicare."

Republicans, who spent the better part of two years emphasizing "reform" of Medicare, now portray themselves as the program's protectors.

"Medicare is a promise and we will honor it," Ryan said on Wednesday. "A Romney-Ryan administration will protect and strengthen Medicare for my mom's generation, for my generation and for my kids and yours."

Medicare, which is expected to become financially insolvent in 2024, covers almost 50 million elderly and disabled people. Soaring U.S. healthcare costs have made it a target in efforts to reduce the federal deficit.

Seniors oppose the Ryan plan by 2 to 1, according to recent polls that also show widespread opposition among all registered voters.

After weeks of campaign warfare, however, the Medicare battle has not translated into an electoral advantage for Obama among seniors, according to some polls.

The Quinnipiac University/CBS/New York Times survey showed elderly voters favoring Romney in Florida, where he led Obama by 13 percentage points, and in Ohio, where he led by eight. Romney also had a slight lead in Wisconsin.

"Seniors are split, especially in retiree-rich swing states like Florida, and I don't think they're going to change their opinions about who to vote for based on Medicare," said Susan MacManus, who teaches government and international affairs at the University of South Florida.

BOOMERS, THE REAL TARGET

Baby boomers are more supportive of Obama generally. Voters aged 50 and 64 favored Obama by four to six percentage points in Florida, Ohio and Wisconsin, according to the Quinnipiac poll. They were also more likely than seniors to trust the president on healthcare and Medicare.

Obama spokesman Adam Fetcher declined to discuss the campaign's Medicare strategy in detail, but he acknowledged that the game plan extends beyond senior citizens.

"The unpopularity of the Romney-Ryan Medicare voucher plan is an opportunity for the president to close the gap among seniors as well as other demographics," he said.

Analysts say boomers who are not yet retired could be more receptive than seniors because their retirement is a worrisome unknown. "Boomers are the real target group," MacManus said. "A lot of them have had everything they planned for turn upside down with the recession and housing prices going down. They're the ones in turmoil, and they haven't heard they're going to be exempt from any reforms."

An AARP survey released this month shows retirement to be a major source of anxiety among boomers, with large majorities expressing doubts about their ability to retire comfortably.

Democratic strategists say the Obama campaign will focus on selected races for the U.S. Senate and House where, analysts say, the party could have its best shot at delivering a policy message capable of influencing voters.

"It helps Obama, especially in the swing states that he's got to win. If they can make the case against a Republican Senate candidate on Medicare, that also hurts Romney and helps Obama," said Jennifer Duffy of the Cook Political Report, a nonpartisan group that analyzes U.S. politics.

The political calculation will figure into Democrats' spending on House and Senate race television ads leading up to the November 6 election.

"If we thought Medicaid was an issue that appealed only to senior citizens, we wouldn't be going up on television with it," said a Democratic campaign official.

(Editing by Fred Barbash and Douglas Royalty)

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