While Senate Democrats continue to fight for records pertaining to President Donald Trump's U.S. Supreme Court nominee Brett Kavanaugh—threatening on Thursday to sue the National Archives for documents detailing his time working for the second Bush administration—a new poll from CNN revealed Kavanaugh is the least popular nominee in more than three decades.

The survey (pdf), conducted by SSRS and published Thursday, found that only 37 percent of Americans want the Senate to confirm Kavanaugh, which CNN noted "is the lowest in polling dating back to Robert Bork's nomination by President Ronald Reagan in 1987." Forty percent of those polled said they oppose Trump's nominee, while 22 percent said they have no opinion.

Kavanaugh's record has raised fears about what his confirmation could mean for reproductive rights, the environment, human rights, workers, healthcare, net neutrality, and the Russia investigation, among other key issues. Those concerns have led to a massive #StopKavanaugh effort led by advocacy groups that celebrated the poll results on Twitter:

BREAKING: New CNN poll shows that not only is Brett Kavanaugh extreme, he's wildly unpopular. The momentum is on our side, and we're not done yet. #StopKavanaugh https://t.co/FubjBoERsi — NARAL (@NARAL) August 16, 2018 NEW POLL: Kavanaugh's nomination to the Supreme Court has the lowest public support since Robert Bork in 1987. Public opinion is on our side! #StopKavanaugh #SaveRoe https://t.co/cOzk2p0STA — UltraViolet (@UltraViolet) August 16, 2018

As CNN outlined:

Republicans are broadly supportive of Kavanaugh: 74 percent would like to see him confirmed, while Independents split 38 percent to 38 percent and Democrats largely oppose his nomination (67 percent say he should not be confirmed).... Women, in particular, are notably opposed to Kavanaugh's nomination, and it's not just partisanship driving the difference. Just 28 percent of women say the Senate should vote in favor of confirming Kavanaugh, compared with 47 percent of men. That gender gap extends to Democrats (6 percent of Democratic women support confirmation vs. 22 percent of Democratic men), and Independents (28 percent of women vs. 47 percent of men). There's a far smaller gap between GOP women (71 percent) and men (77 percent).

The results come as Democrats are engaged in a fight with the National Archives and former President George W. Bush's legal team over records related to Kavanaugh's time serving as Bush's staff secretary. Senate Minority Leader Chuck Schumer (D-N.Y.) said Thursday that the National Archives has 20 days to comply with a Freedom of Information Act (FOIA) request to turn over hundreds of thousands of pages—otherwise, Democrats will file suit.

Since Republicans have chosen secrecy over transparency, Democrats issued a FOIA request to the National Archives, seeking the full gamut of Kavanaugh’s records, including from his time as Staff Secretary. We stand ready to sue the Archives for his full records, if necessary. — Chuck Schumer (@SenSchumer) August 16, 2018

Schumer, who also told reporters on Thursday that he plans to meet with Kavanaugh in the coming days, is under mounting pressure to keep Democrats united in opposing the candidate. Even if all Senate Democrats—and the Independents who caucus with them—vote against Kavanaugh, blocking his nomination still requires convincing a couple of GOP senators to withhold their support of his confirmation.

Kavanaugh opponents are focusing on Republican Sens. Lisa Murkowski (Alaska) and Susan Collins (Maine), while also keeping a close watch on Democratic Sens. Heidi Heitkamp (N.D.), Joe Donnelly (Ind.), Joe Manchin (W.Va.), Claire McCaskill (Mo.)—who have all met with or plan to meet with Trump's nominee, and are known for siding with Republicans on major votes.

The Senate Judiciary Committee is scheduled to begin hearings for Kavanaugh on Sept. 4.