The Massachusetts Senate race just got more interesting: Elizabeth Warren, the former head of the Consumer Financial Protection Bureau, hinted strongly that she might take on incumbent Republican Scott Brown.

In a blog post on Blue Mass Group, Ms. Warren, a Harvard law professor, wrote: “I spent years working against special interests and have the battle scars to show it – and I have no intention of stopping now. It is time for me to think hard about what role I can play next to help rebuild a middle class that has been hacked at, chipped at, and pulled at for more than a generation—and that that is under greater strain every day.”

Ms. Warren, who’s been the subject of speculation all summer, will announce her decision after Labor Day, according to a Massachusetts Democrat familiar with the matter.

So far the Democratic field is crowded, but no clear front-runner has emerged to challenge Mr. Brown.