That's right. Mallard Fillmore is a Libertarian. The comic strip that bellwethers movement conservatism -- with its endless stream of personal jabs and caricatures of liberals that seem pulled out of a time vault (seriously, the figure most satirized so far this year is Teddy Kennedy, with four Chappaquiddick jokes in two months), with its approving citations of Michelle Malkin and regular paeans to William F. Buckley, with its complete lack of criticism of any right-wing figure anywhere, with its blurb proudly proclaiming its "conservative bias" -- has found a new word to replace the label "conservative". Chantel is a liberal, and Mallard is the opposite -- a "libertarian."
Given that the strip has shown no other sign of disagreement with GOP-talking-points positions (except to chastise GOP politicians for behaving too much like Democrats!), what this boils down to is that Mallard, despite believing all the same things they do, is ditching the label "Republican" in order to go over and stand with the Cool Kids. And rest assured that's all it is, political camouflage. For example, actual Libertarians think the government has as much business lecturing Americans about Mallard's beloved "moral values" as it does about Mallard's despised political correctness.
Man. When even Gipper the Talking Points Duck is too busy ducking the label that best describes his political stance in order to go stand Over Here Away From Bush And The GOP, you know that the party is political damaged goods.
As a minor side note, the strip where Mallard "liberals, liberals, democrats, democrats, liberal democrats" Fillmore chides a coworker for conflating Republicans and conservatives is (I'm sure unintentionally) the funniest strip he's ever done.
* Granted, the competition is very fierce.