Wilkerson's Democratic challenger is...
Sonia Chang-Díaz, a JP resident who 1) used to be an aide to state senator Cheryl Jacques; 2) ran Angus McQuilken's failed campaign to replace Jacques a few years back, 3) currently works at the Barbara Lee Family Foundation, and 4) sits on the board of Mass Vote.
The McQuilken connection won't inspire tons of confidence in anyone who watched that race, but primary blame for McQuilken's defeat probably lies with the candidate himself, who was no great shakes. In contrast, the Barbara Lee connection could be extremely helpful as Chang-Díaz wages her sticker campaign. Lee is a woman who gets shit done; witness her big assist in Andrea Cabral's win over Steve Murphy. If Lee is on board here, Wilkerson should be seriously worried.
You can read Blue Mass. Group's take on Chang-Díaz here.
Finally, don't rule out the possibility of another Democrat jumping into the race. If you live in the Second Suffolk and have the faintest interest in being a state senator, this is one hell of an opportunity.