Personally, I don't think the Democrats trust her. In that regard it wasn't the Obama administration who poisoned the well for her ... it was her own husband's administration.
Remember -- this is a woman who spent something like six years serving on the board of directors of Wal-Mart, of all companies. I think Democrats see the Clintons the same way Republicans do: as opportunists and frauds. She doesn't have Bill Clinton's political skills to overcome that baggage.
I’ve also heard that there are other ambitious Democrats, who see a Hillary candidacy blocking their paths for the next 10 years.
Reason being, if Hillary wins the presidency in 2016, then she will run for re-election in 2020. Meaning that the next open Democrat presidential primary contest would be in 2024, ten years from now.
I’ve heard some behind the scenes action is taking place based on not wanting the Clintons to block others for the next 10 years. Just another piece of the political puzzle going forward.