I'd expect FB to have more of a pro-life contingent than say, Twitter, but still small to my perspective. (I live in a purple district in a purple state, so it's not uncommon for half and half workplaces to exist).

I'd also expect that the majority of FB's right-leaning employees are of a SV libertarianish bent, and most of them are pro-choice or apathetic.

FB strikes me as a company with a very mercenary, self-interested workforce more than a partisan one.