Although former Secretary of State Hillary Clinton is far and away the frontrunner for the Democratic nomination in 2016, many Democrats apparently are looking for an alternative. Will it be Martin O'Malley? Stu Rothenberg at Roll Call makes a pretty compelling case for the former Maryland governor to be the biggest obstacle to Clinton's pursuit of the White House, at least from the Democratic side.
Hillary Rodham Romney? Keep an Eye on O’Malley
...At first glance, the idea of a backbencher mounting even a moderately interesting challenge to Clinton is preposterous. After all, she will have the deepest war chest in history, begins with a lengthy résumé of accomplishments, has a flood of endorsements and institutional support, and holds the “first woman president” card in her hand...
On the other hand, someone like former Maryland Gov. Martin O’Malley, who apparently is seriously considering a run for the Democratic nomination, has the potential to become at least an interesting alternative to the former first lady and secretary of State, both to reporters and progressive activists.
Attractive and youthful, O’Malley is a former two-term mayor of Baltimore and governor of Maryland. Personable and with a ready smile, he plays the guitar and sings. His liberal credentials are unassailable, his Irish charm obvious.
In spite of his personal qualities and political positions, I doubt O’Malley, 52, would have much of a chance — or any chance — of overtaking Clinton. But, unlike Sanders or Webb, he could well be credible enough to generate a boomlet among progressives, leading to a flurry of media stories about Clinton’s weaknesses and vulnerabilities. And, were that to happen, it would be an important moment for the Clinton campaign...
Rothenberg also mentions Vermont Senator Bernie Sanders and former Virginia Senator Jim Webb, but doesn't seem to think they have much of a chance:
Sanders, 73 and in his second Senate term, is so far on the left he isn’t a credible alternative. And Webb, 69, isn’t nearly progressive enough for Clinton’s critics and doesn’t seem to enjoy politics or people all that much. Both men often appear frustrated, angry and humorless...
At this time in 2007, first-term U.S. Senator Barack Obama was probably given about as much of a chance of getting the nomination as O'Malley is being given now. That's not to say O'Malley can do what Obama did, but he's probably as likely a candidate as anyone else to get the Democratic nod over Clinton in 2016.