David Letterman is the liberal talk-show host who appeared on his own show on CBS, Late Show with David Letterman, among other projects. Senator John McCain (R-AZ) appeared on the show during the 2008 presidential campaign.
Attacks on Sarah Palin
True to his liberal nature, Letterman has repeatedly mocked Alaska's conservative Republican former governor Sarah Palin, since she came into the public eye as a 2008 vice-presidential candidate. In June 2009, while Palin was attending a benefit for those with autism in Westchester, New York, Letterman escalated these attacks in a particularly degrading fashion, describing Palin as looking like a "slutty flight attendant" and falsely claiming that her 14-year-old daughter, Willow, was "knocked up" by New York Yankee Alex Rodriguez on the field at a Yankees game. Letterman has since claimed that he meant to make fun of Willow's 18-year-old sister Bristol, believing it was she who had attended, rather than Willow. Letterman has since given some sort of apology for the incident with Palin's daughter that Palin has accepted. CBS has since kept its production contract with Letterman, giving him a continued venue for his liberal rants against Republicans and conservatives.
The resulting outrage led several large companies to drop advertising on his show. This has not stopped his attacks on Sarah Palin. His September 29th, 2009 show had a top 10 list mocking Sarah's $63,000 dinner for charity.
Letterman has acknowledged that he had sexual relations with several staff members. One individual, Robert "Joe" Halderman of Norwalk, CT., threatened to go public with the allegations of the relationship with his girlfriend Stephanie Birkitt, unless Letterman paid him $2 million.  
In a 2005 extortion attempt, police revealed a plot by house painter Kelly Frank to kidnap Letterman's baby son Harry, for a $5 million ransom.
- Letterman reveals extortion attempt, Variety, October 1st, 2009
- Woman in Letterman Case Lived with Suspect, TMZ, October 2, 2009