DETROIT (AP) -- Days before a pivotal primary, Republican presidential candidate Mitt Romney said Friday he would raise the eligibility age for Medicare as he looks to show he's willing to curtail government benefits in the long run.
It was a new detail in a major campaign speech that was otherwise short on new policy ideas. Romney delivered the speech to the Detroit Economic Club at the cavernous and largely empty Ford Field, where the Detroit Lions play football.
"With these commonsense changes, we will have fixed our balance sheet," Romney told the crowd of about 1200, who occupied just a portion of the field itself as tens of thousands of stadium seats sat empty.
Romney walked through much of the economic plan he had already unveiled Wednesday ahead of a GOP debate. He's proposing 20 percent cuts to the marginal individual tax rates. He also wants to lower corporate tax rates to 25 percent from 35 percent. On Friday, he said he wants to raise Medicare eligibility age by one month per year and eventually tie the age to life expectancy.
Romney's campaign rests on a foundation of economic know-how, and he presents himself as a lifelong businessman who has the skills to put an end to the worst recession in decades.
With the speech, he was looking to draw contrasts with Democratic President Barack Obama. Romney paints Obama as looking to create an "entitlement society" where the former Massachusetts governor claims he wants an "opportunity society."
But Romney is facing an unexpectedly tough challenge from GOP rival Rick Santorum in his native state of Michigan. Santorum won contests in Colorado, Missouri and Minnesota on Feb. 8 and rose in polls afterward.
Santorum has been emphasizing his blue collar roots and looking to appeal to tea party and socially conservative voters in Michigan. Opinion polls show voters aligned with the tea party are more likely to support Santorum than Romney.
Romney has tried to cut into that support, courting tea party voters in suburban Detroit on Thursday night with an indictment of President Barack Obama as a man who is "comfortable living with trillion-dollar deficits." The former Massachusetts governor went out of his way to praise them as part of his courtship.
"I appreciate the work you're doing. I appreciate your willingness to get out of your homes," he said Thursday.
But his speech Friday served to highlight his support among wealthy voters - and his family's own personal wealth. The crowd was formally dressed and offered polite applause as Romney said he planned to lower all tax rates but make sure the wealthiest Americans still shoulder the same percentage of the burden.
When he referenced "higher income" taxpayers, he pointed at the crowd.
Then, as he closed his remarks, he pointed out that his wife, Ann, drives "a couple of Cadillacs." Ann Romney has two Cadillac SRX cars, one in Massachusetts and one in California, a spokesman said.
In his speech, Romney stayed entirely away from the social issues that have helped propel Santorum's rise.
Backed by ads attacking Santorum from his own campaign and from Restore Our Future, an outside group that supports him, Romney has made evident gains in the past week in Michigan. But numerous polls show that Republicans who say they support one of the candidates could change their mind, and surveys also suggest that the state is divided along geographical regions.
Romney outruns Santorum in the Detroit area, but the situation is reversed in much of the rest of the state, in some surveys.
That creates the possibility of something of a split decision next Tuesday in which Romney wins the popular vote but Santorum emerges with more delegates. Most of them are awarded, two at a time, to the winner of each of the state's 14 congressional districts.
In all there are 30 delegates at stake in Michigan next week, and 29 in winner-take-all Arizona.
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