Photo

A “super PAC” set up by allies of Senator Rand Paul of Kentucky raised just over $3 million in the first six months of the year, according to a report filed with the Federal Election Commission on Friday — far less than most of the outside groups backing Mr. Paul’s rivals for the Republican presidential nomination.

Almost half of the money came from a single donor: George Macricostas, a Nevada-based businessmen and technology entrepreneur. Most of the rest came from Jeff Yass, an investor from Pennsylvania, who contributed $1 million.

A handful of other donors — some of them also raising money directly for Mr. Paul’s campaign — made six-figure contributions, including Robert Arnott, a California investor, and Kenneth Garschina, a longtime Paul backer in New York.

The super PAC, America’s Liberty, filed more than a week before the official deadline. It had about $2.7 million in cash at the end of June, according to the filing.

The haul was relatively low in the high-dollar, high-stakes world of super PACs, which have taken center stage in this year’s Republican primary contest.

A super PAC backing Jeb Bush announced this month that it had raised $103 million, while Senator Ted Cruz of Texas is backed by a network of super PACs that brought in $37 million. Two groups supporting Senator Marco Rubio of Florida brought in a combined $32 million.

Which Presidential Candidates Are Winning the Money Race See how the latest fund-raising numbers from the campaigns and outside groups stack up.