FCC is a good route, but if there are no show SPONSORS, there IS no show, FCC investigation or not.
Most efficient route is to call show sponsors and as them if they WANT to pay for rape promotion.
Here are David Letterman’s sponsors:
Aveeno https://www.aveeno.com/contact-us.jsp;jsessionid=ICzq9MKfCJMvYNQPalV7EWJ+CJY
Canon http://www.usa.canon.com/templatedata/AboutCanon/ciwofloc.html
Charmin (Owned by Proctor & Gamble) http://pg.custhelp.com/cgi-bin/pg.cfg/php/enduser/ask.php?p_sid=49Z6U*zj&p_accessibility=0&p_redirect=&p_sp=cF9zcmNoPTEmcF9zb3J0X2J5PSZwX2dyaWRzb3J0PSZwX3Jvd19jbnQ9NzUsNzUmcF9wcm9kcz01OSZwX2NhdHM9MCZwX3B2PTEuNTkmcF9jdj0mcF9wYWdlPTE*&p_srch=1&p_prods=59&p_pv=1.59
Citibank https://online.citibank.com/US/JRS/portal/contactus.do
Downey (also P&G) http://www.downy.com/en_US/contactus.jsp
Hellmans https://secure.hellmanns.com/contact_us.aspx
Lexus (Owned by Toyota) http://www.lexus.com/contact/
Nissan Motors http://www.nissanusa.com/apps/contactus
Rogaine http://www.rogaine.com/men/contact-us
Ambien CR https://contactus.sanofi-aventis.us/default.aspx
Chase https://www.chase.com/ccp/index.jsp?pg_name=ccpmapp/shared/assets/page/contactus
Ford http://www.fordvehicles.com/help/contact/
Hotels.com http://www.hotels.com/faqs.do?reqType=getQuestions&cmsFaqId=
Listerene (Johnson & Johnson) https://www.listerine.com/contact-us.jsp;jsessionid=o9dUC7PE892Iut-YH7ibH32Z1Wk
Mazda http://www.mazdausa.com/MusaWeb/emailMazda.action
Old Navy (Owned by The Gap) http://oldnavy.gap.com/customerService/info.do?cid=3332&mlink=5151,1004621,3&clink=1004621
Samsung http://www.samsung.com/us/info/contactus.html
T-Mobile http://www.t-mobile.com/Contact.aspx