WASHINGTON (AP) -- For all the recent diversions over Medicare and abortion, Republican presidential candidate Mitt Romney is still running a campaign that paints with a broad economic brush in hopes of rallying voters on jobs and fiscal policy. President Barack Obama, by contrast, is painting by the numbers, filling in the Democratic landscape step by demographic step.
The president's pointillist approach has been on sharp display in recent weeks as he has alternately tailored his campaign speeches and his ad campaigns to women, older voters and, most recently, new young voters who may not have been old enough to cast a ballot four years ago.
In each case, Obama has used Romney and his running mate, Rep. Paul Ryan of Wisconsin, as foils, arguing that their policies would limit women's health care choices, force seniors to pay more for Medicare and cut back on student loans.
Ryan's place on the Republican ticket has given Obama the opportunity to draw attention to Medicare, singling out Ryan's proposal to overhaul the health care program for older Americans and drawing Romney into a skirmish on an issue that favors Democrats. Obama's courtship of women got an unexpected boost by the eruption over Missouri Senate candidate Todd Akin's remarks about rape and abortion, prompting an unexpected debate on that social issue.
As a result, the presidential campaign is taking shape as a contest between Democratic interest-group politics on one side and the Republicans' single-issue referendum on Obama's stewardship of the economy on the other.
"We've got major economic debates, but that's not the only place where we have debates," Obama told donors in New York on Wednesday.
To be sure, Obama offers his own predominant story line, casting Romney as an advocate of the rich and an adversary of the middle class. But within that narrative there is room for made-to-order arguments that are specific to the various components of the Democratic coalition.
Romney's camp says that approach allows Obama to skirt his economic performance.
"It's a far cry from the 2008 campaign where Obama sought to build a grand coalition of voters," Romney senior adviser Kevin Madden said. "Instead, because he has such a poor record on the economy, he's been relegated to micro-targeting individual demographics and playing them against each other."
Young voters are high on Obama's outreach effort. The enthusiastic grass-roots work of young people was a significant factor in Obama's 2008 victory. This time, the high schoolers of 2008 are now eligible to vote, presenting an untapped source of support.
"I'm going to need your help -- young people especially -- I'm going to need your help," Obama told a crowd at Capital University in the battleground state of Ohio on Tuesday. "And when you leave, I'm asking you to grab 10 friends -- make sure they're registered, too."
Obama will continue wooing students next week when he campaigns in the university towns of Ames, Iowa, Fort Collins, Colo., and Charlottesville, Va.
Obama has been driving the education issue by casting Romney as out of touch with students and their families. He has repeatedly reminded audiences that Romney once suggested that students could meet their financial needs by simply borrowing from their parents or shopping around for the best deals.
For Obama, courting young people is not so much about securing their vote -- he leads Romney 54 to 38 percent among voters younger than 35 in the latest Associated Press-GfK poll. Instead, it is about firing up those young voters and boosting their numbers.
Obama has a harder time with older voters. Romney leads Obama among voters over the age of 65, a group that votes in high numbers. To convince them, Obama was prepared to link Romney to plans by congressional Republicans to change the Medicare system and offer the next generation of older Americans a direct government payment they could use to purchase their own health care.
By selecting Ryan, the chief budget writer in the House, as his running mate, Romney initiated the Medicare debate even sooner than Obama had planned. Obama argues that Romney and Ryan would change Medicare "as we know it," making a direct pitch to older voters, even though the changes proposed by Romney and Ryan would not affect current retirees.
"Their plan makes seniors pay more so they can give another tax cut to millionaires and billionaires," Obama said, campaigning in New Hampshire last Saturday.
Yet, after focusing on the issue for a few days with an ad and speeches, Obama has virtually dropped the issue from his campaign repertoire. Addressing students Tuesday, he only mentioned Medicare once. By Wednesday, it had disappeared from his speech altogether.
For one thing, the campaign doesn't want to overexpose the issue now, in the heat of summer and with many voters still not focused on the presidential contest. Romney's camp is glad to have the issue debated now rather than later, and it launched a preemptive critique of the changes to Medicare that are in Obama's broad health care plan. But Obama's camp has indicated it will push the issue to the front once again as the election nears.
Obama leads Romney among women. But suburban women comprise a significant segment of the sliver of voters who are still on the fence. To that end, Obama has been airing ads in a number of competitive states making his case for women by citing Ryan's voting record on funding for Planned Parenthood and abortion. The ads are airing in Colorado, Nevada, Virginia, Ohio, Florida and Iowa.
Obama aides note that Obama gets his biggest applause lines when he declares: "We're not going back to the day when women didn't have control of their own health care choices. We're going forward, we're not going back."
Then Missouri's Todd Akin weighed in. The Republican congressman who is challenging Democratic Sen. Claire McCaskill told an interviewer that women's bodies could prevent pregnancies in cases of "legitimate rape." Akin's remarks caused a furor and denunciations from across the political spectrum. But Akin defied calls from Romney and other Republican leaders to step down from the race.
Obama seized the moment to draw attention to his differences with Romney and Ryan over women's health. And it dovetailed with the ads Obama was already running. The Obama camp has been happy to let the controversy play out.
"Having this debate and having the conversation about it is one we certainly welcome," Obama campaign spokeswoman Jennifer Psaki said.
About a week earlier, a dozen or so female volunteers in the Romney campaign's Colorado headquarters were calling women in the state. As the phone bankers fished for votes, Colorado state Rep. Libby Szabo, a Republican, dismissed the Obama campaign's arguments that women should fear the Romney-Ryan ticket's stance on reproductive issues.
"I don't think that's the biggest challenge we face today as women," she said. "The biggest challenge is, is my job safe so I can feed my children? That's the winning issue."
AP Deputy Director of Polling Jennifer Agiesta and Associated Press writer Nicholas Riccardi in Colorado contributed to this report.