Martin O'Malley has now made the announcement, accompanied by a video (below) suggesting he intends to run as a Democrat. That's not really news, unless one compares it to the analogous Clinton video, a sort of Democratic version of "Morning in America."
Cheap shot at Hillary Clinton aside, we turn to the horse race. Charlie Peters makes an interesting observation about Senator Sanders, which seems to be in sharp contrast to O'Malley, when he writes
Here's what I think. I don't think he's running to push Hillary Rodham Clinton to the left, or to affect the debate. I think Bernie Sanders is running for president because he wants to be president. He has issues that need addressing, and a constituency for them, and if there's any other qualification for a candidate, I don't know what it is. And, anyway, in that context, he is no more (or less) plausible than just about the entire Republican field....
If someone like Bernie Sanders thinks he can be president, and he's willing to bring his politics into the soul-numbing marathon that is a presidential campaign, there is something there that is quite good for the country.
Former governor O'Malley is willing to bring his politics, clearly bolder than Clinton's and less so than Sander's, into the marathon that is a presidential campaign, though he probably is less willing to enter something soul-numbing. As Maggie Haberman reported the day before O'Malley's formal announcement
When Martin O’Malley began actively exploring a presidential run in 2013, he reached out to Hillary Rodham Clinton, the frontrunner for the Democratic nomination, to let her know. She told him he should do what he needed to do.
So as Mr. O’Malley, the former governor of Maryland, prepared for his Saturday campaign kickoff, he reached out to Mrs. Clinton again.
The call between the two was brief and cordial, according to two people briefed on it, neither of whom was authorized to describe the private conversation. Aides to both Mr. O’Malley and Mrs. Clinton declined comment.
As he prepared to challenge Mrs. Clinton for the Democratic nomination, Mr. O’Malley has been reluctant to criticize Mrs. Clinton or to draw a pointed contrast with her.
Haberman concludes "Mr. O’Malley is expected to highlight his positions on issues important to the party’s liberal base and try to appeal to Democrats who may be looking for an viable alternative to Mrs. Clinton." If all goes right for Martin O'Malley, a reasonably young male, he'll receive consideration next summer as the running mate for Clinton, whom he expects to be the candidate, and who is not reasonably young or male. There is nothing illegal about this strategy, but it is a reminder that there already is a viable candidate, one approximately 480 miles north of O'Malley's Baltimore.