A group of Republican donors and operatives has been the hidden hand behind some of this campaign’s most controversial advertisements attacking Kamala Harris and bolstering Donald J. Trump.
Over $100 million was raised and spent over the past four years by a political nonprofit called Building America’s Future, according to four people briefed on the group’s work. And in the presidential race, the group is expected to have spent more than $35 million to peel off liberal support for Ms. Harris from vital demographic groups, such as younger men and Muslim Americans, and to get third-party candidates on ballots.
Building America’s Future will be publicly revealed in federal campaign finance filings on Tuesday as the sole funder of two super PACs that have disclosed little about their backers. The first, Duty to America PAC, has targeted young male voters and Black voters whom they are hoping to persuade to vote for Mr. Trump.
The second, Future Coalition PAC, has gone after Ms. Harris in Michigan by highlighting her positions that are pro-Israel, along with the Jewish faith of her husband, Doug Emhoff.