KC is actually a pretty diverse town and politics isn't nearly as much in the forefront as what I found with people on the west coast (portland, seattle, sacramento). I find it far easier to make friends here in KC than on the west coast as a result*, not to mention that there are a lot of liberals here. KU is in Lawrence which is a liberal town and not far from KC. If you live in KC proper (not the 'burbs), you'll find a ton of liberal, atheist, child-free 20 & 30 somethings.

People don't really talk religion... sure you'll see anti-abortion billboards when you drive across the state, but you see that everywhere. I saw religious signs & billboards when I grew up in Oregon; not any different here.

*edit: what I mean here is that people don't try to suss you out before deciding whether to talk to you or hang out with you. I have religious & politically conservative friends here, as well as those who are far more liberal than I am, but we rarely ever talk about politics or religion.