Not only is health care overhaul at stake but Washington's ability to solve any problems, he said.
"We need courage," Obama said three times to loud cheers.
"The American people want to know if it's still possible for Washington to look out for their interests, for their future. So what they're looking for is some courage," he said. "They're waiting for us to act. They are waiting for us to lead. They don't want us putting our finger out to the wind. They don't want us reading polls."
"As long as I hold this office, I intend to provide that leadership, and I know these members of Congress are going to provide that leadership," he said. "I don't know about the politics, but I know what's the right thing to do. And so I am calling on Congress to pass these reforms, and I'm going to sign them into law."
Early in his remarks, Obama noted the presence of Rep. Dennis Kucinich, D-Ohio, who's undecided on how he will vote on the upcoming health care compromise.
An audience member shouted "Vote yes!"
"Did you hear that, Dennis?," Obama asked, and prodded the audience member to "Go on say that again.
Kucinich, who flew on Air Force One to Cleveland with Obama, earlier told reporters that he would not comment on his current position on the health care bill.
"I'm looking forward to hearing what he [Obama] has to say," he said.
The White House says health care reform would help people like Canfield by lowering costs, ensuring more competition and making sure insurers are not able to deny coverage because of previous bouts with serious illnesses such as cancer.
"Lying in a hospital bed, worrying about how you're going to pay for your bills -- that's hard. I know. My mother went through that," the president said last week in St. Louis at a fundraiser for Sen. Claire McCaskill, D-Mo.
"Once the bill is implemented, she's not going to have to worry about an insurance company discriminating against her on the basis of a preexisting condition," White House press secretary Robert Gibbs told ABC News March 4.
But Republicans say such anecdotes are not proof that this bill should become law. They say it will be a disaster and Democrats are forcing it through the Congress and on the American people.
"There will be a price to be paid to jam a bill through. The American people don't like using a sleazy process," Sen. Lindsey Graham, R-S.C., said Sunday on ABC News' "This Week." "If they [Democrats] do this, it's going to poison the well for anything else they would like to achieve this year or thereafter."
Democratic leaders are unsure whether they have enough votes to pass the health care legislation. A total of 216 votes are required in the House to pass the bill. That's the total number of Democrats who voted for the bill last year, but since then, some have backed off amid concern that supporting the controversial bill would hurt their chances in this year's mid-term election. Others cite cost issues while some liberals, such as Rep. Dennis Kucinich, D-Ohio, say it doesn't go far enough.
But Americans like Canfield don't know if they can wait.
"I went from feeling A-OK to really bad," Canfield told ABC News from the hospital.
Canfield said she knows she will be facing "a huge hospital bill" since she had to drop her individual health insurance from Anthem Blue Cross and Blue Shield of Ohio after its most recent premium increase.