If someone makes a political comment, they'll be rapidly downvoted by those who are emotionally (not necessarily rationally) invested in the counterargument.

You are almost certainly mistaken. Explicitly political content isn't generally downvoted because of investments in opposing positions (I do recall one possible exception, but lack of cluefulness and a bad-faith debating style were at least as much to blame there): it's downvoted because it's perceived, and correctly so, as presenting a threat to unbiased discussion.

It's well within site norms to post content with political implications, at least outside of issues relating to gender and to a lesser extent race (which are uniquely disruptive exceptions as best I can tell). People do: there's content supporting any number of possible political stances, including some seriously weird ones that don't as far as I know have actual movements attached to them. But you need a data-driven approach for this to work, and as far as possible you need to refrain from explicit political advocacy in your presentation. Rhetoric will not avail you: at best you'll get linked to the post you happen to be commenting under. More likely you'll simply be downvoted into oblivion.