"There's no alternative . . . "

. . . to Hillary Clinton as the Democratic nominee.

I think this is basically nonsense.   Elizabeth Warren, Joe Biden, and any number of current or former Democratic governors or senators are as or more qualified than Obama was in 2008, or for that matter than several of the Republican candidates.   I think this is essentially a smokescreen being put up by the Clintons to distract attention from her obviously flawed rollout.   If Clinton were to drop out, within six weeks you would see a series of imperfect but very credible candidates.  

I just don't think it's convincing.