OBAMA JOKES BLACK BANNED

The L.A. Times offers an explanation for the dearth of mainstream TV Obama humour:

Obama has cast so many political humorists into a bad spot because he lacks the obvious defining qualities -- both mentally and physically -- that transformed previous Oval Office occupants into comedic catnip. He doesn't have a strong regional accent and didn't have a strange job before his political rise (former peanut farmer Jimmy Carter). He doesn't fall down (Gerald Ford). He is not regarded as aging or forgetful (Ronald Reagan). He hasn't been dubbed a "wimp" (George H.W. Bush). He is not tainted by scandal (Clinton). He doesn't stumble over the English language (George W. Bush).

Alternatively:

You have to remember that most comedy writers on these shows are more liberal than conservative.

Liberal and mostly unfunny -- try watching Letterman.