There are bacteria that live in our clouds (although I believe it's a lifecycle where they come down at some point). The current theory is that Venus was habitable at some point a billion years ago (prior to runaway greenhouse gas cycle). So theoretically there could have been some extremophile bacteria. They've also (possibly) found phosphine which is difficult (but not impossible) to explain w/o life. I don't think anyone's offering odds of life on Venus, but I'm pretty excited they're sending this probe.