Massachusetts Senate candidate Elizabeth Warren won’t get to face Scott Brown in November without a fight from a fellow Democrat.

Marisa DeFranco, a 41-year-old immigration lawyer from Middleton, is the last Democratic challenger to Warren standing. DeFranco, who is running for office for only the second time (she unsuccessfully ran for city council in 2001), is on track to earn a spot on the Democratic ballot at this weekend’s state party convention in Springfield–but only if she can win 15 percent of the delegates–to force Warren to a primary election on September 6.