Rep. Michael Capuano, D-Mass., conceded before the race was even officially called. That’s unusual for a 10-term incumbent, but Boston City Councilor Ayanna Pressley clearly bested him, winning nearly 59 percent of the vote.

It could be a sign something unusual is afoot inside the Democratic Party this year. Women candidates have fared well in the primaries. Liberals have also scored some upsets against the party establishment. The Tea Party arguably started in Massachusetts when Republican Scott Brown claimed Ted Kennedy’s former Senate seat in a 2010 special election — eight years later, are we witnessing a Tea Party of the Left?