When President Obama announced that he would nominate Massachusetts Senator John Kerry to helm the State Department, I assumed that this would clear the path for Scott Brown to reenter the Senate, just a few months after losing his re-election bid to Elizabeth Warren. But Brown isn’t running, and Republicans have few options. Former state Senator Richard Tisei was one possible contender, but he announced on Saturday that he would not be running for the seat. And this morning, former governor Bill Weld released a statement saying the same — he will not enter the race.

Simply put, there aren’t many options left for the Massachusetts Republican Party. There’s been some indication that former Lieutenant Governor Kerry Healey would join the fray, but her electoral record leaves much to be desired — she hasn’t been popular with the state’s voters.

At this point, the race to replace John Kerry is a fight between Democrats: Rep. Ed Markey has support from the Democratic establishment — including the Democratic Senatorial Campaign Committee, Vicki Kennedy, and Kerry himself — but he faces a primary challenge from Rep. Stephen Lynch, who brings considerable support from unions and other labor groups. At the same time, however, Lynch opposes abortion, making him an odd duck among Massachusetts Democrats.

Because of Brown’s surprise victory in 2010, it’s tempting to treat the Republican in this race as a viable contender. But if the current situation is any indication, Brown’s win was sui generis and not much of a guide. Remember, he initially ran in a wave of anti-Obama discontent, in a special election with lower-than-normal turnout, against a listless, uninspiring opponent. Against a strong Democratic candidate in a normal environment, Brown lost handily. And so, whichever Republican runs to replace John Kerry will have to face a deep blue electorate, in a state that gave a double-digit margin to President Obama. The GOP could overcome that, but it’s not likely.

Jamelle Bouie is a staff writer at The American Prospect, where he writes a blog.