Hillary Clinton late Sunday raised the possibility of appealing a decision by Democratic Party leaders on convention delegates from Florida and Michigan, threatening to prolong her nomination fight against Barack Obama.

The remarks, made in an interview with The Washington Post, indicated the US senator from New York was not ready to throw in the towel, even through the campaign dynamic and delegate numbers indicated her chances of winning the nomination were growing increasingly slim.

"We reserve the right to do it. But I haven't made a decision yet," Clinton told the newspaper.

On Saturday, a panel of the Democratic National Committee restored the states of Michigan and Florida to its presidential convention, but with only half of their voting power.

Democrats in the two states had been initially denied the right to seat their convention delegates because they broke party rules by holding their primary votes in January.

Clinton gained a net 24 delegates from Saturday's two-state compromise, which was not nearly enough to secure her nomination.

But even as momentum and the delegate count favoured Obama, she vowed in the interview to continue her political fight.

"I am focused on winning the nomination," she said. "So I'm going to stay focused on what is the business at hand, which is making my case to the delegates, and there'll be time, oh, way in the future to consider the campaign, because it's still very much alive and ongoing."

With Democratic voters essentially split and the primary contest approaching its final stage on Tuesday, Clinton made clear she was determined now to focus on influencing convention superdelegates, or top Democratic Party officials, who in effect will decide the nomination this year.

While the superdelegates have been trending toward Obama in recent weeks, the New York senator made clear she believed the trend can be reversed.

"One thing about superdelegates is they can change their minds," she told The Post.