In October, documents surfaced that appeared to contradict a key story told by Sen. Elizabeth Warren on the campaign trail. In her telling, Warren’s “dream job” as a public school teacher ended in 1971 when the school principal noticed she was “visibly pregnant,” a form of employment discrimination that was legal and common during that era. On October 7, a conservative website presented archived documents that appeared to challenge that narrative, including the minutes of a meeting in which the school board had voted to extend Warren’s tenure and another in which the board notes that Warren herself resigned from the job.

The story spread like wildfire, moving from conservative publications to major newspapers. Even Kellyanne Conway, a counselor to President Donald Trump, weighed in on the controversy to suggest that the Democratic candidate had lied about her life story. More records seeming to challenge Warren’s narrative emerged, including a 2007 interview in Berkeley, California, in which Warren appeared to say that she left teaching on her own accord to raise her child and seek additional education credentials, as well as a contemporaneous newspaper story about Warren leaving the school “to raise a family.”

Warren has stood by her story that she was “shown the door” because of her pregnancy. “When I was 22 and finishing my first year of teaching, I had an experience millions of women will recognize. By June I was visibly pregnant — and the principal told me the job I’d already been promised for the next year would go to someone else,” Warren said on Twitter last month.

But how did these documents surface in the first place? According to the results of an open records request, an opposition research group known as America Rising had requested documents from the Riverdale Board of Education in New Jersey just weeks before the news appeared. It asked for “Warren’s employment records,” as well copies of other records requested from the school board from the previous two years.

In response to the request, a school official provided America Rising with the school board minutes that became the basis for the story that erupted the following month, along with emails from a Wall Street Journal reporter, who had requested similar records in April.

America Rising — which is affiliated with a political action committee, a public relations firm, and a for-profit research company, as well as several news websites — has been backed over the years by Republican donors, including hedge-fund billionaires Paul Singer and Ken Griffin, private equity investor John Childs, and banker Andrew Beal.

America Rising did not respond to a request for comment. The organization did not claim direct responsibility for the Warren story, but touted the documents as soon as they appeared online via an allied conservative website called the Washington Free Beacon. Free Beacon is also funded by Singer.

America Rising is known for attempting to dig up dirt on politicians, journalists, and activists on behalf of donors’ interests. The group went after journalist Jane Mayer, shopping negative information about the New Yorker writer following the publication of her book “Dark Money.” In 2016, America Rising focused on environmentalist Bill McKibben, dispatching its team to obtain thousands of documents from McKibben’s past and to follow the Vermont-based writer, filming him at public events, as well as while grocery shopping and sitting in a church pew. This year, Definers Public Affairs, an affiliate of America Rising that shares the same staff, decided to rebrand following revelations that the company had been retained by Facebook to orchestrate a campaign to smear its critics.