Among the really big "old school" names
Hillary ? No. The people reject her and so do I
Al Gore ? No. He has already stated that the answer is "no."
Wes Clark ? No. Not charismatic enough and simply not VP material all-around
Bill Bradley ? Say yes ! Talk about a powerful choice. Age 64.
John Edwards ? Pretty good, but not as good as Bill Bradley.
Russ Feingold ? He probably will decline and he's a powerful force in the Senate now.
Wiki for Bill Bradley
William Warren "Bill" Bradley (born July 28, 1943) is an American hall of fame basketball player, Rhodes scholar, and former U.S. Senator from New Jersey and presidential candidate, who opposed Vice President Al Gore for the Democratic Party's nomination for President in the 2000 election.
Sorry, I don't know much about names such as Kathleen Sibelius.