The 2012 presidential election could be more important than the 2008 election, President Obama warned voters at a series of campaign stops in his hometown of Chicago on Wednesday.

Obama, speaking during a teleconference with supporters ahead of a pair of Democratic National Committee fundraisers in Chicago, said that the next election "in some ways may be more important than the last one."

"The future is going to be determined by this election," Obama said.

But the president's reelection could also be a tougher fight than his landslide victory nearly three years ago.

After a messy fight over raising the nation's debt limit — capped by a deal that nobody seems to like — Obama is being hounded by critics on the right and the left. His approval ratings are near all-time lows. Gallup's tracking poll found only 42 percent approve of the president, one point above the lowest level in that poll.

The president touched on criticism from the left concerning the recently passed debt-limit increase compromise. Since Sunday, when Obama and congressional leaders announced the deal, some Democrats have criticized both Obama and the package for failing to include liberal sticking points like adding revenues in the form of tax increases on wealthy Americans and protecting entitlement programs from benefit cuts.

"All the progressives out there, I want you to understand, we can't just ignore this debt and deficit," Obama said.

At the second, smaller fundraiser later that night, Obama again touched on the deal to raise the debt ceiling. 

"Obviously, we've just gone through an extraordinary week in Washington, an extraordinary two weeks in Washington," Obama said. "I think this episode was just a severe example of what's been going on for quite some time and it's part of what led me to run for president ... and it's part of the reason why, hopefully, all of you are here tonight, because you recognize we've still got some more work to do."

Obama added that throughout the negotiations Republicans were successful in striving for their goals.

"I give the other side credit," Obama said. "They are single-minded in their focus in wanting to cut programs and shrink government."

Obama spoke at a packed Democratic National Committee fundraiser at the historic Aragon Entertainment Center, where he was introduced by his former chief of staff, Rahm Emanuel, now the mayor of Chicago.

Chicago-native musicians Herbie Hancock and Jennifer Hudson headlined the event.

Obama's visit to his hometown came a day before his birthday. 

"I am beaming in from Chicago. Having a little birthday celebration in my hometown," Obama said during the teleconference.

At the Aragon, in front of a crowd of 2,400 packed into the un-air-conditioned ballroom, Emanuel introduced his former boss.

"I can tell you that when it comes to doing what's right for the country, he never takes the easy road," Emanuel said. "If he thinks it's right, he'll pay any political price to do it — I can tell you that because I first came to tell him to take the easy road."

Hudson then led the crowd in singing "Happy Birthday" to the president.

Obama used the occasion to express his commitment to entitlement programs that Democrats have traditionally championed.

"It's true that I turn 50 tomorrow," Obama said, "which means that by the time I wake up, I’ll have an email from AARP ... asking me to call President Obama and tell him to protect Medicare."

Obama's visit to his hometown ahead of his birthday comes as he gears up for a bus tour through Midwest battleground states in which he will talk about his administration's job-creation efforts.