Top Sanders supporter in Congress backs Clinton
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Rep. Raúl Grijalva, one of Bernie SandersBernard (Bernie) SandersGrassroots America shows the people support Donald Trump Five former Obama ambassadors back Buttigieg Both sides were wrong about Mueller report, and none of it will likely matter for 2020 MORE's few supporters in Congress, has endorsed Hillary ClintonHillary Diane Rodham ClintonGrassroots America shows the people support Donald Trump Ex-FBI official: 'Links and coordination' with Russia happen everyday Ex-FBI agent: Americans should be 'disgusted' by Russian interference in Mueller report MORE as Democrats continue to push for unity around her presidential campaign. 

The Arizona congressman and co-chairman of the House Progressive Caucus was the first member of Congress to support the Vermont senator's presidential bid back in October. He has been a key ally for Sanders, serving at times as a cable news surrogate and as one of the campaign's picks for the party's platform drafting committee. 
Grijalva lauded Sanders's campaign in a statement released Thursday and said the country is "already much stronger" for his efforts. But he argued that coalescing around Clinton is the best choice for Democrats. 
"With voting completed in the final Democratic Primary, it is now time for the Democratic Party to unify. For all of us who supported Bernie from the beginning, whether we considered ourselves progressives or independents or just Americans tired of being on the outside looking in, the most important thing now is to beat Donald TrumpDonald John TrumpGrassroots America shows the people support Donald Trump Trump speaks to rebel Libyan general attacking Tripoli Dem lawmaker: Mueller report shows 'substantial body of evidence' on obstruction MORE in November," he said.
"Hillary Clinton has the capacity and the instincts needed to carry forward what has been started. I support her and will do what I can to help ensure her victory. I firmly believe that her victory will only come when she and the Democratic Party articulate the themes this movement has so powerfully expressed."
NBC News first reported the endorsement Thursday morning.
The endorsement puts the congressman in an interesting spot on the platform committee — he's tasked with advancing the Sanders campaign's goals but is now backing Clinton. Grijalva briefly addressed that issue in his statement, arguing that "unity will not be realized if the millions of voters who supported Bernie Sanders feel taken for granted."
"It won’t be enough to just accept the merit of his ideas. This is in no small part Bernie Sanders’ party also. His team, his supporters and his movement must — and will — be integrated into the future of the Democratic Party at every level," he said.