Gilchrist is the founder of The Minuteman Project, the group known for patrolling the US-Mexican border in its effort against illegal immigration. He seems to be engaged in a written back-and-forth with syndicated columnist Ruben Navarrette Jr. In response to an "angry e-mail" from Gilchrist, Navarrette wrote this. Now Gilchrist has written this.
Basically, Gilchrist is trying to sell the Minutemen as a diverse group of patriots who are in favor of legal immigration. Navarrette says they are "misfits" who carry lawn chairs and coolers of beer. To further spread the word about the Minutemen, they, of course, have a website and Gilchrist has made personal appearances, including this visit to The Colbert Report.