Bowie, Maryland (CNN) -- President Barack Obama on Thursday challenged young Democrats at an election rally for Maryland Gov. Martin O'Malley, saying political pundits were predicting they lacked the enthusiasm of Republicans.
"They say their followers are more energized," Obama told the rally at Bowie State University. "They say you might be willing to let the other folks who left the economy in a shambles go back to Annapolis and go back to Washington."
Adding that he was betting on the young voters to prove the pundits wrong, Obama told the crowd: "Don't make me look bad."
O'Malley faces off in November against Republican challenger Robert Ehrlich. In 2002, Ehrlich become the first GOP governor of Maryland since Spiro Agnew, but he was defeated in his 2006 re-election bid by O'Malley, who was mayor of Baltimore at the time.
A recent Washington Post poll indicates that O'Malley leads Ehrlich by 11 points among likely voters. Other recent surveys have suggested O'Malley holds a single-digit advantage.
Democrats greatly outnumber Republicans and independents in Maryland, and the key to an O'Malley victory would be to ensure that Democrats go to the polls.
Obama sought to rally a strong Democratic turnout, attacking Republicans as an obstructionist party that seeks a return to failed policies of the past.
"Make no mistake, this election is a choice, and that choice could not be clearer," he said, framing it as Democrats pushing to move forward on economic recovery and global competitiveness versus Republicans pledging to follow the same agenda that caused the recession.
"I bring this up not to relitigate the past; I just don't want to relive the past," Obama said to laughter from the crowd. "I don't want to go through that mess again."
Noting the "Pledge to America" governing platform recently unveiled by House Republicans, Obama called it "the same old snake oil they've been peddling to Americans for years."
Joining him on the stage were O'Malley, Maryland's two Democratic senators -- Ben Cardin and Barbara Mikulski -- and other top Democrats from the state.
Obama interrupted his speech twice to seek help for people in the audience who collapsed.
"I think we might have had somebody faint down here, so if we got the paramedics," Obama said halfway through his remarks under bright afternoon sunshine. "They'll be all right. Just make sure you give them some space. And if somebody has a bottle of water, you might want to give it to them."
A few minutes later, near the end of his remarks, Obama again noted a member of the crowd in distress. He called for people to let the stricken person sit down, then said: "Remember, next time you come out here, eat something and drink something" beforehand.
Prince George's County Fire Department officials later told CNN they were treating at least two dozen people at the university for fainting and dehydration.
Bowie State University is the oldest historically black college/university in the state and its located in Prince George's County, which has a large African-American population and a heavily Democratic electorate.
O'Malley supported then-Sen. Hillary Clinton in the 2008 Democratic presidential primaries, but he became a major backer of Obama during the general election. Obama won two-thirds of the vote in Maryland in the presidential contest.
CNN's Paul Steinhauser, Tom Cohen, Paul Courson and Vito Maggiolo contributed to this story.