Sanders and Clinton raised roughly similar amounts for the month — $26.2 million and $26.6 million respectively, according to Federal Election Commission filings and the campaigns.
Sanders spent heavily to contest April primaries against Clinton. He won a significant victory in Wisconsin but lost in New York, which his campaign had set up as a critical test of strength. The New York primary was particularly costly for both campaigns, but Sanders outspent Clinton in expensive television advertising.
Both campaigns saw their fundraising decline during the month as the Democratic primary winded down. Sanders raised a whopping $44.7 million in March and closed the month with $17.4 million on hand. Clinton raised $29.3 million in March and ended that month with $29 million on hand.
The Clinton campaign's cash-on-hand figures include funds raised with the Democratic National Committee and state party committees through the Hillary Victory Fund, which can accept larger six-figure contributions from individual donors. The Clinton campaign says the funds will be used to support state party committees in the general election.
“Thanks to the support of more than 1.2 million people, we are in strong financial shape as we head into the final primary contests and prepare for the general election,” said Robby Mook, Clinton's campaign manager. "This will enable us to continue investing in people who will mobilize millions of voters and help Democrats running up and down the ballot.”
The main super PAC backing Clinton, Priorities USA Action, raised $8.6 million taking its total haul to date to $121 million. The group announced another $45 million in pledges.
Major donors to the group include Cheryl and Haim Saban who gave $3 million in April. The Univision chairman and his wife have already given $7 million to the super PAC. Other million-dollar donors include S. Daniel Abraham -- founder of weight-loss brand Slim-Fast and Alexander Soros, son of George Soros.
While Sanders was low on cash, he continued to see a significant amount of money coming from donors who have given less than $200. So far, he has received 62 percent of his money from those small donors, compared with approximately 21.3 percent for Clinton.
"The average contribution to the senator’s campaign is around $27," the campaign said in a statement. "Only 5 percent of Sanders' total came from donors who have given the maximum $2,700 an individual may donate to a candidate."
Clinton and Sanders are preparing to compete in the large and expensive California primary on June 7.