The email has a standard form, which reads like this:
"I have been a member of your district for years and have never asked for anything - not a new traffic light, not lowering the sales tax, not even to think of the children! But today I ask you as a proud American to agree to be interviewed by Stephen Colbert on The Colbert Report's "Better Know A District" segment. Since 2005, Stephen has interviewed at least 60 representatives, including Rep. Barney Frank (D-MA), Rep. Aaron Schock (R-IL), and Rep. Jackie Speier (D-CA). Your appearance would put our district on the map and make your constituents proud. Thank you for your consideration."
There's also room to type a personal message.
If Matheson or Bishop would appear with Colbert, they couldn't do much worse than Rep. Jason Chaffetz did just after taking office in 2009. During that interview, Colbert beat Chaffetz in a leg-wrestling competition.