Hillary Clinton's campaign has struggled recently to present a credible way that she could win the Democratic presidential nomination, considering that Barack Obama leads her in the earned delegate count, the popular vote, and has pulled nearly even with her in the number of super-delegates who have committed themselves to his nomination.  Most observers say that only a miracle could bring her even to Barack Obama in the popular vote.

Now, Hillary Clinton's closest surrogates seem to be abandoning her efforts, effectively telling the news media that there is virtually now way that she can win.

(CNN) -- Two prominent supporters of Hillary Clinton suggested Thursday the New York senator needs to best rival Barack Obama in the total popular vote to have any chance at winning her party's presidential nomination.

In separate media interviews, New Jersey Gov. Jon Corzine and Pennsylvania Rep. Jack Murtha both indicated they believed Clinton will be unable to convince enough superdelegates to support her if she finishes second to Obama in both the pledged delegate count and the popular vote.

Speaking on CNBC, Corzine suggested it won't be enough for Clinton to argue she deserves the nomination because she has won more crucial swing states than Obama -- a talking point the senator's campaign has long argued.

"I think it would be a very hard argument to make," Corzine said of that position. "I'm a very aggressive supporter of Senator Clinton, but I think you need at least a popular vote."

Corzine also suggested he himself may cast his superdelegate vote for Obama should Clinton fail to win the popular vote, though the New Jersey governor insisted he thought Clinton would come out on top in that count if the Florida and Michigan contests were counted.

Murtha echoed Corzine's sentiments in an interview later Thursday, saying, "Clinton has to win Pennsylvania...She has to be ahead in the popular vote to have any chance at all of getting this nomination."  CNN