I think T's in general tend to be a left wing kind of bunch. This is just my experience of the ones I personally know and not empirical evidence. I get the need to feel morally aligned with your T - I am reassured by my T's obvious shock and horror at the Brexit vote which he didn't conceal when I raised it (though I bet if I was pro Brexit he wouldn't have expressed that).
The truth is, your T will likely not tell you and you will likely never know so you have to make a decision as to whether the not knowing is acceptable for you. Does it have a direct impact on therapy? If it does can you work on that in therapy?