Yes, opposition to gay marriage was so mainstream that even Barack Obama campaigned supporting Clinton's Defense of Marriage Act. Even in the Democratic primaries, as late as 2008, being pro gay marriage was seen as a liability.

I don't know that it's painted as far right as much as conservative (which it is) and by some as bigoted.

The Overton Window moves. Upper marginal tax rates above 90% were not just a position but the actual law in USA during the 1960s, but now are seen here as "far left". Seatbelt requirements were initially felt to be over-intrusion by government, and are now seen by almost everyone as just common sense. And so on and so forth.