President Obama and Republican presidential nominee Mitt Romney appealed directly to Hispanic audiences at a Univision forum in Miami.
Immigration reform, a hot-button issue in this election, was front and center.
In June, the president issued an executive order allowing young people brought to the United States illegally to apply for deportation referrals.
But he was repeatedly pressed about his failure to keep a 2008 pledge of comprehensive immigration reform within the first year of his presidency.
"A promise is a promise, and with all due respect, you didn't keep that promise," the Univision moderator Jorge Ramos challenged.
"I am happy to take responsibility for the fact that we didn't get it done," Obama replied. "But I did not make a promise that I would get everything done a hundred percent when I was elected as president."
"What I promised was that I would work every single day as hard as I can to make sure that everybody in the country, regardless of who they are, what they look like, where they come from, that they would have a fair shot at the American dream. And that promise I kept," the president said.
Meanwhile, the audience sought specifics of Romney's immigration policy.
"Are you going to deport them or not? I'm not that clear," Ramos pressed the former governor.
"I'm not in favor of a deportation, mass deportation effort, rounding up 12 million people and kicking them out of the country," Romney said. "I believe people make their own choices as to whether they want to go home, and that's what I mean by self-deportation."
"I will actually reform the immigration system and make it work for the people of America," he vowed.
Recent polls show Obama leads Romney among Latino voters by a 2 to 1 margin.