I don't care what religion or political views they have. Its a workplace, if either person can't check it at the door then that's the problem to deal with.
Honestly its pretty insulting to both of the people involved for you to assume so strongly that they couldn't be professional that (a) you never give them the chance and (b) you chose to hire only the one who you agree with (or disagree with the least).
the people talking to you are talking about something very different than simply "political beliefs that you disagree with"
the appropriate level of capital gains tax at the 80th percentile is a political belief that you can tweet about in your personal time and allowing there to be a civil relationship with your colleagues in a professional environment. this is a political belief that reasonable people can disagree with.
asserting the supremacy of the white race is not a political belief that you can tweet about in your personal time while still allowing a civil relationship with your colleagues in a professional environment. this is not something that reasonable people can disagree with.
Honestly its pretty insulting to both of the people involved for you to assume so strongly that they couldn't be professional that (a) you never give them the chance and (b) you chose to hire only the one who you agree with (or disagree with the least).