Tonight they are one of the sponsors of the first GOP Presidential debate. Another sponsor is the Oath Keepers who according to Think Progress:
The Oath Keepers’ website is riddled with paranoid rhetoric about government officials “disarm[ing] the American people,” “confiscat[ing] the property of the American people, including food and other essential supplies,” and “blockad[ing] American cities, thus turning them into giant concentration camps.” In early 2008, the Oath Keepers’ founder warned that a “dominatrix-in-chief” named “Hitlery Clinton” would impose a police state on America and shoot all resisters. After primary voters chose a different candidate, the Oath Keepers simply rewrote their paranoid fantasy to include a taller, African-American lead.
Another group called the Exodus Mandate which believes public education is evil and all children should either be educated in a Christian environment or home schooled.
Note: These organizations are sponsors of a pre-debate rally. There is a difference, nuanced though it may be but the fact remains that extremist groups feel a lot more comfortable in the environs of the mainstream GOP and vice versa.