Obama has begun to hit Romney hard on Medicare, tying his rival to Ryan's budget proposal to overhaul the health care plan for older people. The issue is particularly important in competitive states such as Florida, Iowa and Pennsylvania that have large elderly populations.
Seeking to drive older voters away from Romney, Obama has seized on Ryan's plan to shift future retirees into a system dominated by private insurance plans.
"The truth is, I think they know it's not a very popular idea," the president said Saturday while campaigning in New Hampshire. "You can tell that, given the fact that both of them have proposed to voucherize the Medicare system. I guess they figure the best defense is to try to go on offense."
But Romney and Ryan anticipated the Obama reaction and went after Obama's health care overhaul, which includes reductions in Medicare spending of $700 billion over 10 years. While those cuts come from health providers, not from benefits to seniors, Romney and Ryan are still portraying them as harmful to seniors.
The Romney team also says the timing of the Medicare debate benefits them.
"It's actually fortunate for us that it's being litigated in August as opposed to October," Newhouse said. "If it comes up again in October, it's not going to be new information."
The Romney campaign says calls for smaller government resonate with independent votes, particularly undecided suburban women. The GOP used the issue in 2010 when it regained control of the House. Indeed, shifting views among independents on the role of government were a big difference between the 2008 and 2010 electorates, according to exit polls.
In 2008, 43 percent of independents said government should do more to solve problems, while 49 percent said government is "doing too many things better left to businesses and individuals." In 2010, that split was 28 percent do more to 65 percent saying government is overreaching.
But some Republican strategists warn that a debate over government spending has risks. They say undecided voters are all for fiscal discipline if it's linked to economic growth, but they recoil if they perceive spending cuts as austerity measures that would affect them.
"The fiscal battle injected into the national discourse is really going to hinge on who can sell growth and who is selling austerity," said Republican pollster Wes Anderson, who is polling in several congressional districts in states that are competitive in the presidential contest.
AP Deputy Director of Polling Jennifer Agiesta and Associated Press writer Ricardo Alonso-Zaldivar contributed to this report.
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