And Committee to Restore America’s Sovereignty was formed in May by a group including former Ben Carson aide Doug Watts. It hasn't filed fundraising reports with the Federal Election Commission yet, but Watts said this week it has raised $2 million so far.
Several other donors are discussing where to invest money, including representatives of casino billionaire Sheldon Adelson, according to Politico.
Trump boasted of his independence from big donors during the Republican primary, and after the Washington Post reported on ties between his campaign and one super-PAC, he disavowed the group and it disbanded last year.
Clinton, for her part, has had the benefit of big-money groups from the beginning of her campaign. Priorities USA Action, the main pro-Clinton super-PAC, has raised $76 million during this election cycle, and had $47 million on hand as of April 30.