President Barack Obama has officially begun his campaign to win a second term in the White House, six months before Election Day. The president kicked off the campaign Saturday on college campuses in two key states.

Mr. Obama's first campaign rally was at Ohio State University in Columbus. He urged those who supported him four years ago to do so again. "We will finish what we started. We are still fired up. We are still ready to go," he said.

Next, a similar rally at Virginia Commonwealth University in Richmond.

Ohio and Virginia are two of the states where analysts believe this year's election may be decided.

The condition of the US economy could be the deciding issue, especially in manufacturing-heavy states like Ohio, where the president defended his economic programs. "Exports surged. And over four million jobs were created in the last two years, more of one million of those in the last six months alone," he said.

The likely Republican nominee, Mitt Romney says the president is to blame for the sluggish economic recovery. He has also been sharply critical of Mr. Obama's 2010 health care law.

At a campaign rally in Pittsburgh, Pennsylvania on Friday, Romney said the program must be repealed. "First of all, I would take away one of the things that frightens entrepreneurs and innovators and businesses of all kinds from hiring. I will get rid of Obamacare," he said.

The president defended his policy and accused Romney of wanting to move the country backward. "America does not need to re-fight the battles we just had over Wall Street reform and health care reform," he said.

Michelle Obama introduced her husband, as she is expected to do frequently during the campaign. "I will admit, I am a little biased, because I think our president is awesome," she said. Polls show that the First Lady is more popular than the president.

The two rallies on college campuses Saturday are expected to be the first of many for the Obama campaign.

Young voters were an essential part of the coalition that helped elect Mr. Obama in 2008, and he will need their help again this year.

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（来源：VOA 编辑：旭燕）