The Irony of Satire: Political Ideology and the Motivation to See What You Want to See in The Colbert Report -- LaMarre et al. 14 (2): 212 -- The International Journal of Press/Politics
http://hij.sagepub.com/cgi/content/abstract/14/2/212
"no significant difference between the groups in thinking Colbert was funny, but conservatives were more likely to report that Colbert only pretends to be joking and genuinely meant what he said while liberals were more likely to report that Colbert used satire and was not serious when offering political statements."