Sen. Kirsten Gillibrand announced Wednesday that she's ending her bid for the White House.

Gillibrand becomes the fifth, and perhaps highest-profile, Democrat to end her candidacy as a once unwieldy field of candidates vying to take on President Trump begins to thin.

The senator from New York announced the end of her campaign after she failed to meet the Democratic National Committee's polling and donor qualification threshold to appear in next month's debate in Houston.

"After eight incredible months, I'm ending my presidential campaign," Gillibrand said in a video posted to social media announcing her intentions. "I know this isn't the result we wanted. We wanted to win this race. But it is important to know when it's not your time, and to know how you can best serve your community and country"

Gillibrand, 52, launched a presidential exploratory committee in January and formally announced her candidacy in March. She has served as the junior U.S. senator of New York since 2009. She served in the U.S. House from 2007 to 2009.

Her presidential campaign never gained steam.

She achieved 2% support in only one DNC-approved poll — candidates need to meet the 2% mark in four approved polls — and had yet to report receiving donations from at least 130,000 individual contributors, including 400 donors from at least 20 states.

Only 10 of the more than 20 major Democratic candidates vying for the nomination have achieved the threshold. Wednesday is the deadline for candidates to meet the qualification threshold; the DNC is expected to officially announce Thursday which candidates will be on the debate stage on Sept. 12 in Houston.

Gillibrand’s campaign centered on gender equity, and she unveiled a series of policy proposals to demonstrate her commitment to the issue.

“Women in America are on fire,” Gillibrand said in her closing statement during the first Democratic debate. “We've marched, we've organized, we've run for office. We've won. But our rights are under attack like never before by President Trump and Republicans who want to repeal Roe v. Wade, which is why I went to the front lines in Georgia to fight for them.”

As she exited the race, Gillibrand said her campaign put "the civil rights of women front and center."

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Gillibrand also touted climate change, marijuana legalization, and protecting LGBTQ rights as major features of her platform.

But Gillibrand struggled to breakthrough in the historically large field. As of Wednesday, her national polling average was 0.1%, according to RealClearPolitics. She raised $3 million in the first quarter of her campaign and $2.3 million in the second, a significantly smaller haul than those of top-tier candidates.

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Gillibrand follows Rep. Seth Moulton of Massachusetts, Washington Gov. Jay Inslee, former Colorado Gov. John Hickenlooper, and Rep. Eric Swalwell of California in bowing out of the race.

Gillibrand aggressively took on the Democratic frontrunner, former Vice President Joe Biden, over his record on women's rights during the campaign. Most notably, she demanded at last month's debate in Detroit that Biden answer for a decades-old op-ed where the former senator argued against tax credits for daycare for families he believed could afford to take care of children on their own.

"He believed that women working outside the home would ‘create the deterioration of family,'" she said, partially quoting the headline of the op-ed. "He also said that women who were working outside the home were ‘avoiding responsibility."

In an extended back-and-forth, Biden pushed back against the notion that he was anything less than a champion of women over the course of his long political career and took aim at Gillibrand's previous support for him, noting that she was full of praise for his dedication to equality at a 2015 Syracuse University event to raise awareness about campus sexual assault.

"You came to Syracuse University with me and said, ‘It was wonderful. I’m passionate about the concern, making sure women are treated equally,'" he said. “I don’t know what’s happened except that you’re now running for president."

Gillibrand came to the race with a record of promoting gender equity as a senator. In 2013, Gillibrand led a yearlong charge to overhaul the Pentagon's sexual assault policies. She garnered some congressional Republican support for her push, but it ultimately failed.

In 2017, she called for Sen. Al Franken to resign over allegations that he sexually assaulted multiple women, a campaign that was ultimately successful despite massive opposition from those in her own party by whom Franken was beloved.

In July, The New Yorker published a 12,000-plus word article in which investigative journalist Jane Mayer attempted to fact-check the Franken controversy.

The article received widespread attention, some criticizing it for seeming to exonerate the former senator. Mayer reported that seven current and former U.S. senators who demanded Franken’s resignation two years ago said that they were wrong to do so.

“There is no prize for someone who tries to hold accountable a powerful man who is good at his day job,” Gillibrand said at a town hall event in June, responding to comments said about and by Franken in the article. “But we should have the courage to do it anyway.”

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Gillibrand did earn a bit of viral fame in the second Democratic debate.

“The first thing that I’m going to do when I’m president is I’m going to Clorox the Oval Office,” Gillibrand zinged Trump.

Twitter reported it was one of the top three most talked about moments of the night, and the only one that didn’t involve an exchange with another candidate.

As she ended her candidacy, Gillibrand expressed confidence that the Democrat who emerges will prevail over Trump.

"I believe I can best serve by helping to unite us to beat Donald Trump in 2020," she said.