WASHINGTON — His coffers are feeling the “bern.”

Bernie Sanders’ fundraising slowed dramatically last month following a string of losses, his campaign announced Sunday.

The Vermont senator brought in $26 million in April compared to $46 million in March — signaling the first slow-down of Sanders’ momentum and explanation for his recent staff layoffs.

“There comes a time where you have to look at the reality,” Hillary Clinton told CNN of Sanders’ pathway to the nomination.

Clinton has not yet released her April numbers, but Sanders had consistently out-raised Clinton for the previous three months because of his record-breaking grassroots support. But he’s also burning as much money as he’s raised by investing more in advertising than Clinton.

He began April with $17.5 million in the bank, compared to Clinton’s $29 million.

Despite big losses in New York, Pennsylvania and Maryland, Sanders on Sunday showed no sign of retreat.

“This convention will be a contested contest,” Sanders said at a Sunday Washington D.C. press conference.

Clinton is ahead in the delegate count 2,165 to Sanders 1,357 delegates, but Sanders openly called on party leaders and elected officials – known as super delegates – to switch their allegiance to him in states in state where beat Clinton badly.

“They are going to have to go into their hearts and they are going to have to ask themselves, do they want the second strongest candidate to run against Trump or do they want the strongest,” Sanders said at the National Press Club.

Clinton said she’d aggressively reach out to Sanders supporters to unify the party.

Sanders adviser Jeff Weaver offered conditional support Sunday when asked if the Vermont senator would hit the campaign trail for Clinton is the nominee “Yes,” Jeff Weaver told CNN, quickly adding that the “onus is really on Secretary Clinton to bring the Bernie people to her.”

In Indianapolis Sunday, Clinton shook hands with patrons at local pancake restaurant and later told a rally she wants to create more opportunities for young people, expand technical education in high schools and boost apprentice programs.

She also responded to President Obama poking fun of her appeal to young people at the White House Correspondents Association dinner Saturday night.

“You’ve got to admit it though, Hillary trying to appeal to young voters is a little bit like your relative that just signed up for Facebook,” Obama said. He continued: “Dear America, did you get my poke? Is it appearing on your wall? I’m not sure I’m using this right. Love, Aunt Hillary.”

Clinton tweeted: “@potus Nice job last night. Aunt Hillary approves. #WHCD –H”