As Donald Trump’s party came together, a 28-year-old liberal activist ousted top House Democrat Joe Crowley in the president’s hometown Tuesday night, a stunning defeat that suddenly forced Democrats to confront their own internal divisions.

Crowley, the No. 4 House Democrat and until Tuesday considered a possible candidate to replace Nancy Pelosi as leader, becomes the first Democratic incumbent to fall this primary season. He was beaten by underfunded challenger Alexandria Ocasio-Cortez, a former Bernie Sanders organizer who caught fire with the party’s left wing - Sanders was quick to congratulate her.

In Maryland, Ben Jealous, former president of the National Association for the Advancement of Colored People, defeated Rushern Baker, a veteran politician, in what was seen as another win for liberal Democrats.

Jealous would be the state's first black governor if he can beat popular incumbent Republican Larry Hogan in November.

Bernie Sanders congratulated both progressive candidates after their victories on Tuesday night.

“Ben showed that running a progressive, issue-oriented campaign can bring all working people together in the fight for justice,” Sanders said in the statement. “That's what Ben has done in the primary and that is what a united Democratic Party will do in the general election.”

“What the people of Maryland understand is that we can most effectively oppose Donald Trump's extremism with strong progressive leadership at the state and local level -- and there are few progressives stronger than Ben,” he added.

Sanders also congratulated Alexandria Ocasio-Cortez, a former campaign organizer for Sanders’ presidential campaign, on her shocking primary victory against Rep. Joe Crowley (D-N.Y.).

“She took on the entire local Democratic establishment in her district and won a very strong victory,” Sanders said of Ocasio-Cortez. “She demonstrated once again what progressive grassroots politics can do."