Insurgent Democratic presidential candidate Bernie Sanders will officially pick up his first congressional endorsement Friday at a rally in Tucson, Arizona, from the area’s congressman, Rep. Raul Grijalva, who is also the co-chairman of the Congressional Progressive Caucus.
Sanders has the support of one of four Democratic voters nationally, but — until now — zero out of 232 Democratic members of Congress. Democratic front-runner Hillary Clinton’s lock on the party’s leaders has left little room for endorsements for Sanders or Vice President Joe Biden, should he decide to jump in the race.
Political scientists say endorsements from party elite are the most determinate of success in party primaries, but Sanders has run an intentionally outsider campaign and his campaign believes endorsements are less important than pundits think.
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In an interview with MSNBC Wednesday, Grijalva, whose endorsement was first reported by The Los Angeles Times, said he wanted to make his support for Sanders public before the first Democratic debate next week.
“I support Bernie’s message. I think it’s an important message. It’s a message that has unfortunately been muted for too long,” Grijalva said.








