Whitney Tilson, head of the hedge fund T2 Partners, did not send out a President Obama endorsement to his list of 8,000-plus email contacts to change voters' minds, but to reach the handful of undecided voters out there. Among his arguments in the 14-page message for supporting Obama, Tilson added, "My view is: Obama has gone much too easy on the financial sector." Could such an endorsement cost him investors?