It would be close, but I think I will win: Obama

United States President Barack Obama has exuded confidence in defeating his Republican rival Mitt Romney in the upcoming presidential polls, though conceding that it could be a closely contested one.

"If the election were held today, I think it would be close but I think we'd win. And we now have 99 days left. If I can say that every single day for the next 99 days, then we will be able to embark on the next phase of this journey," Obama said at a campaign event in New York on Monday.

Seeking his re-election, Obama said he has to complete his unfinished agenda in the second term.

"If we can stabilise Europe, position ourselves on education, on science and technology, on energy, and a few other pieces of unfinished business like comprehensive immigration reform, then there's no reason why America should not thrive in the decades to come," he said.

"We also have to get through a campaign, though. And right now, the economy is still rough enough for enough people that this is going to be a close election. I'm confident that we are running a good campaign and will continue to run a good campaign," he said, but acknowledged that he is being outspent by his rival.

"We are being outspent substantially by the other side, and the super PACs are engaging in an experience we have not seen in America democracy for quite some time. They are spending like nobody's business, mostly on negative ads.

"And we're going to have to continue to compete. We don't anticipate that we're going to match them dollar for dollar -- we don't need to. But we are going to have to make sure that we can get our message out effectively," Obama added.