It's official: The National Education Association is putting its muscle, money, and legions of teacher volunteers behind Hillary Clinton in the race for the Democratic presidential nomination.

The endorsement comes despite serious misgivings from some of its affiliates, who were hoping for Vermont senator Bernie Sanders, or at least a slower endorsement process that would give the union more time to extract policy promises from Clinton. (Plus, there's always the chance that Vice President Joe Biden, who has long had a great relationship with the union, may jump in.)

Still, Clinton got the support of 75 percent of NEA's 170 member Board of directors. (She only needed 58 percent.) Three candidates sought the NEA's seal of approval: Clinton, Sanders and former Maryland Gov. Martin O'Malley.

Sanders is surging in the polls in the crucial early states of Iowa and New Hampshire. And in the most recent quarter, he raised nearly as much money as Clinton, mostly from small donors. (Check out this priceless Onion story about how these donations make Sanders beholden to the wishes of, well, elementary school teachers.) Both the New Jersey Education Association and Massachusetts Teachers Association said they won't back an NEA primary endorsement at this time.

NEA's Endorsement Process

But NEA's president, Lily Eskelsen Garcia, sounds pretty excited about the pick. She told Education Week that the union had some great choices this time around.

"All three of these fine people are friends of the NEA, so it wasn't like, 'Who is the bad guy here.' We love all of them," she said.

But the union ultimately settled on Clinton because of what NEA's board saw as a long-standing commitment to children's issues, dating all the way back to her days at Yale Law School, when she took a summer gig bolstering educational opportunities for migrant kids and students in special education.

"Here is a law student who said, 'Instead of going to Wall Street, I'll go to the Children's Defense Fund,' " Eskelsen Garcia said. She ticked off Clinton's other work for kids, including her championship of children's health issues as first lady of Arkansas and first lady of the nation.

Clinton spent over an hour taking questions from NEA's board on issues like standardized testing (as a senator, Clinton voted for No Child Left Behind) and charter schools (Clinton has supported them in the past.)

She handled the questions like a champ, Eskelsen Garcia said. Clinton told members that tests were never supposed to give the whole picture of a child's achievement and that charter schools were meant to help test-drive new ideas that could ultimately benefit public schools.

As for the timing of the endorsement? "This was the right time to impact the primary," Eskelsen Garcia said. The union used the same "transparent" process in making the endorsement it has used for decades, she added.

Social Media Pushback

It's unclear if Clinton's answers will assuage the union's progressive wing, including the Badass Teachers Association, a caucus within the larger union.

"Yes, this could build our power, but at what cost," said Becca Ritchie, who chairs the caucus in a statement. "This does not make us stronger. People feel their voices are NOT heard. This is not a good strategy."

And some teachers and rank-and-file members unhappy with the endorsement have taken their beef to Twitter using the hashtag #NoEarlyEndorsement.

Clinton already has the backing of the American Federation of Teachers. (She and the union's president, Randi Weingarten, go way back.)

The AFT backed Clinton in the 2008 primary, but the NEA didn't endorse anyone. (It backed Obama in the general election.)

And the union may have lived to regret that move when Obama and his now departing education secretary, Arne Duncan, pushed through teacher evaluations tied to test scores, expanded charter schools, and called for states to use dramatic school turnaround strategies that encouraged schools to replace teachers and principals. Clinton, on the other hand, had been urging caution on performance pay. (More on her record here.)

This time around, Democratic candidates have been virtually silent on K-12. Instead, they've been hitting early childhood education, and especially, higher education, hard on the stump.

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