After a rough week, Sen. Bernie Sanders told his supporters he isn't going anywhere. He's counting on a contested convention.

"Let me be very clear. It is virtually impossible for Secretary Clinton to reach the majority of convention delegates by June 14 with pledged delegates alone. In other words, the convention will be a contested contest," Sanders said at a press conference.

Seeing that type of confidence is probably just what his supporters needed after Sanders recently lost four out of five state primaries. Rumors about the future of his campaign started brewing when staffers were fired in states that already held primary elections.

Those staff layoffs may have been a result of changing campaign contributions. In just a month's time, donations plummeted by more than 40 percent.

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His competitor, Hillary Clinton, already seems to be wooing Sanders supporters by releasing an ad that encourages Democrats to come together.

"America is stronger when we are all supporting one another," she said in a campaign ad.

While it's a good effort, it might not work. An April poll showed that a quarter of Sanders supporters say they won't vote for Clinton if Sanders doesn't get the nomination.



RELATED: See the celebrities who support Sanders over Clinton



9 PHOTOS Celebrities who endorse Bernie Sanders See Gallery Sanders vows to push for Clinton's biggest nightmare ... a contest convention Killer Mike of Run the Jewels The rapper has been very vocal within the hip-hop community about his endorsement of Sanders, and even introduced him at an Atlanta rally. Image via Getty Danny DeVito In August 2015, the 'It's Always Sunny in Philadelphia' actor took to Twitter, saying, "Bernie Sanders...you're our only hope Obi-Wan Kenobi". Image via Getty Mark Ruffalo Ruffalo used Twitter to share his political stance on January 17th of this year, saying, "@BernieSanders is preferred 2-1 by young people because they know his means what he says." Image via Getty Susan Sarandon In June of last year, Sarandon posted a video titled 'Flashback: Rep. Bernie Sanders Opposes Iraq War' along with the caption "We need a leader who is courageous and levelheaded in times of crisis:Bernie Sanders ‪#‎Bernie2016‬. The liberal activist has since been seen campaigning for Sanders in Portland, Maine and introducing him on the campaign trail. Image via Getty Belinda Carlisle Back in August of last year, the lead singer of The Go-Go's tweeted, "yes, I switched teams...my candidate!" above an announcement that Bernie Sanders would be joining CNN's State of the Union. Ever since then she has been an avid supporter on social media. Image via Getty Justin Long The 'Dodgeball' actor introduced Bernie Sanders at a campaign event in Des Moines shortly before the Iowa Caucus. Image via Getty Sarah Silverman Sarah Silverman was among other celebs who headlined a fundraiser for the presidential candidate at Hollywood’s Laugh Factory on January 26th. Image via Getty George Lopez After tweeting "WATCHA I Am #feelingthebern. Today I'm proud to officially endorse @BernieSanders for President" late last year, the actor has made headlining appearances at Sanders' fundraising events. Image via Getty Spike Lee After citing his endorsement on a radio show recently, he elaborated on his commitment to Sanders, saying: “Bernie was at the March on Washington with Dr. King. He was arrested in Chicago for protesting segregation in public schools. He fought for wealth and education equality throughout his whole career. No flipping, no flopping. Enough talk. Time for action.” Image via Getty Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

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