HOOKSETT, New Hampshire — Planned Parenthood endorsed Democratic front-runner Hillary Clinton here Sunday, marking the group's first backing of a primary candidate in its 100-year history.
"I have stood with you throughout my life and certainly throughout my career and I promise you this: As your president, I will always have your back," Clinton said to a room full of Planned Parenthood supporters wearing bright pink.
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Reproductive rights have taken center stage in the 2016 race after undercover videos emerged last year showing a Planned Parenthood official discussing the sale of fetal parts. Last week, Republicans in Congress voted to defund Planned Parenthood. (President Obama subsequently vetoed the bill.)
"I shudder to think about what the Republicans would do if given the chance," Clinton said of a potential Republican presidency. "Planned Parenthood should be funded, supported and appreciated — not undermined, misrepresented and demonized."
Clinton mentions women's health and Planned Parenthood in almost every speech and one of her biggest applause lines comes when she vows to defend the non-profit.
Cecile Richards, president of Planned Parenthood, said the organization did interviews with all of the Democratic candidates but Clinton had "overwhelming support."
"I can't ever remember a greater champion" for women's rights, Richards told NBC News.
She explained that the non-profit made their endorsement now because it's never before seen a cycle where every Republican front-runner has "taken aim" at women's rights, calling them the "most extreme pack of candidates ever."
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Richards also pointed to Clinton's voting record as a senator and her commitment to making women's health "front and center in her campaign" as reasons for backing her.
"She so clearly understands and supports women equality," Richards said. "The stakes have never been higher."
With less than a month to go until the New Hampshire primary, Richards made clear that the group had a sense of urgency in announcing its endorsement. A new NBC/WSJ/Marist poll shows Clinton is neck-and-neck in the Granite State with Sen. Bernie Sanders of neighboring Vermont — Sanders is leading, but within the margin of error.
This article first appeared on NBCNews.com.