Obama Takes Lead in Superdelegate Tally

If Clinton decides to fight on, Panetta advised that she "should remain on issues, they shouldn't engage in personal attacks. … Whether the winner wins will depend an awful lot on how the loser loses."

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There are indications that Clinton is taking a hard look at her options. She has scheduled a meeting Wednesday -- the day after the West Virginia primary -- with her campaign's major financial backers at her Washington mansion.

Stephanopoulos said there was also "lots of very quiet waltzing behind the scenes with intermediaries representing Sens. Clinton and Obama" to engineer a "dream ticket" with Clinton as Obama's vice president.

"I should say there's an expectation that Sen. Obama is reluctant to go down this road for a host of reasons, but others are making the case this is the most powerful ticket for the Democratic Party," Stephanopoulos reported.

For many Democrats, however, Conan O'Brien had it right.

In discussing the states where the two candidates were favored, the comedian quipped, "Hillary is favored in the state of denial."

ABC News' Karen Travers contributed to this report.