COLUMBUS, Ohio (AP) -- Heading into the homestretch of the midterm elections, President Barack Obama is targeting key Democratic constituencies as he tries to energize voters and build up Election Day turnout among his supporters.
The groups Obama is targeting mirror those that helped him win the White House: young people, African-Americans and women. A crucial element of the president's strategy in the two weeks before the Nov. 2 election is finding a way to get first-time voters from 2008 to head back to the polls even though Obama's name isn't on the ballot.
Speaking before a lively crowd of 35,000 during a Sunday night rally on the campus of Ohio State University, the president sought to recapture the enthusiasm of his presidential campaign, urging Democrats not to give up in the face of polls predicting sweeping defeats for the party in November.
"You can defy the conventional wisdom, the kind that says you can't overcome the cynicism of our politics," Obama said, his voice hoarse from three straight days of campaigning.
The White House said Sunday's crowd was the largest Obama had spoken to since his inauguration.
Obama was joined in Ohio by first lady Michelle Obama, their first joint campaign appearance since the presidential election. The first lady has been on a campaign swing of her own, putting a personal spin on the election.
"When I think about the issues facing our nation right now, I think about what that means for our girls," Mrs. Obama told the crowd.
The president has been blunt in recent campaign stops, acknowledging that with 9.6 percent unemployment, the sputtering economy makes this election season difficult for Democrats.
"It's hard because we've been through an incredibly difficult time as a nation," Obama said Sunday. "We've gone through a tougher time than any time in the lifetime of most of us."
Sunday's rally at Ohio State was one of five the president was scheduled to attend ahead of Election Day, all designed to remind the Democratic base of the enthusiasm Obama inspired during his presidential campaign.
The five rallies are all in states Obama won during his presidential bid, and all in states with competitive midterm races: Wisconsin, Pennsylvania, Ohio, California and Nevada. Though Democratic officials say the president is casting a wide net and trying to reach the whole of the Democratic party, some rallies do target specific constituencies.
In Madison, Wis., late last month, Obama targeted young voters at the University of Wisconsin. Officials hoped last week's rally in Philadelphia reached African-Americans, many of whom came to the polls for the first time in 2008 to support Obama. Democratic candidates like Pennsylvania Senate hopeful Joe Sestak need high turnout in urban areas like Philadelphia if they're to overcome stiff Republican opposition.
At an event Thursday in Seattle, Obama will focus on how the economic crisis has affected women. White House deputy communications director Jen Psaki said Obama will argue that women who may have benefited from administration initiatives like the small business lending program would suffer under Republican leadership.
Obama is also using backyard meetings and televised town halls, including one broadcast on MTV, BET and CMT last week.
White House officials insist the president's coast-to-coast campaigning is making a difference.
"There's an excitement about what this president is trying to do. There's an energy around it," Obama spokesman Robert Gibbs said Sunday on NBC's "Meet the Press."
But polls suggest Obama's winning coalition from 2008 is crumbling. About one-quarter of those who voted for Obama are voting Republican in November or are considering doing so, according to an Associated Press-Knowledge Networks poll.
Equally as dispiriting for the White House: Just half of Obama voters say they'll definitely show up to vote Nov. 2, while two-thirds of those who voted for Republican John McCain in the 2008 presidential election say they're certain to vote.
Democratic officials say the president is still the best messenger to encourage his party to get to the polls. Following three straight days of events in Delaware, Massachusetts and Ohio, Obama heads West for stops in Portland, Ore., on Wednesday, Seattle and San Francisco on Thursday, Los Angeles and Las Vegas on Friday and Minneapolis on Saturday.
Obama probably will spend Election Day in the nation's capital, and has requested an absentee ballot to vote in his home state of Illinois.