“They’re a pack of thieves,” Trump told Breitbart News as he was leaving Nashville’s Rocketown facility. He had just finished delivering a high-energy speech to an overflow crowd of more than 1,000 people.

Trump was attending the annual convention of the National Federation of Republican Assemblies, which describes itself as “the grassroots Republican wing of the Republican Party.”

“They [the Club for Growth] came to my office looking for money. I turned them down. That’s why they’re after me,” Trump told Breitbart News.