Someone else viewed as unbeatable has a hail-Mary opponent from the progressive left -- and we're not just talking about Gavin Newsom and Chris Daly! That's right -- the stridently anti-war soldier's mom Cindy Sheehan has declared her candidacy against San Francisco's House representative, Speaker of the House Nancy Pelosi. Sheehan says she's running because Pelosi didn't move to impeach Bush by July 23. She's running as an independent and, along with the anti-war thing,......