Matt Phillips reports from the Clinton campaign plane.

Even with her decisive victory in the Puerto Rican primary Sunday, by some estimates Sen. Hillary Clinton still needs to win more than 80% of the remaining superdelegates to have a prayer of winning the nomination. That is, of course, if superdelegates who've already publicly endorsed Sen. Barack Obama stick with their pick. On a brief press conference held aboard her campaign plane Sunday night, Sen. Clinton hinted that options remain for superdelegates, even those that have already endorsed her rival.

"One thing about superdelegates is they can change their minds," Clinton told a gaggle of reporters in the aisle of the plane. "With us in the front of the cabin is a superdelegate who went from me to Sen. Obama and now is back with me, in the course of, you know, a matter of weeks." A campaign spokeswoman later informed the cabin that the superdelegate she was referring to is Kevin Rodriguez, a DNC member from the Virgin Islands, who was accompanying her on the flight from San Juan. The campaign had previously announced his support. "I think it's only now that we're finishing these contests that people are going to actually reflect on who is our stronger candidate. And I believe I am. And I'm going to make that case," Clinton said.

Clinton also indicated that she considers the DNC's new number denoting the finish line of this historic primary contest, 2,118, as contingent on her decision on appealing the Saturday ruling of the Democratic Party's Rules and Bylaws Committee decision on Michigan. The campaign reserved the right to do so following the ruling.

"We're going to decide how to proceed and depending on what the outcome of that decision is we'll either mount a challenge or not. But obviously it would have an impact on the number of delegates necessary to clinch the nomination," she said.