Politics should not be a consideration, but one needs to negate an oppressive, negative office atmosphere.
Also is he advocating political platforms/positions???Fed regulations against that kind of behavior. Hatch Act of 2939 (amended 2012) prohibits Fed employees from engaging in some political activity.
Then again..what is your position in the office as a new employee? As so many on this thread have warned...you may have to grin and bear it. Proceed cautiously, if at all, in the near future.