Let's, uhm, be a bit realistic here. You're almost NEVER going to be turned down for a job if you're an atheist, because (a) jobs don't have the right to ask you your religion, and (b) there's no point in talking about your religion unless it is a religion-based job. (And, at that point, I can kind of see a very Christian-focused company maybe wanting people who are actually, you know, Christian.) If a company doesn't hire you because of your religion, and it wasn't a case of you causing serious problems centered around religion, that's putting that company in the position of getting their asses sues to hell and back.
As far as politics, I live in Nebraska, close to the Bible Belt and a pretty conservative / republican state, and absolutely an atheist could get elected to a government job. Unless you're running for president, your religion almost never comes up. Now, if you make a big deal about being an atheist, could that hurt your chances? Sure. But, for example, this very heavy Republican state that I live in has elected Democrats many times, because they were the right man for the job. I think most logical people would vote for a "known atheist" if he was clearly the right man for the job.
Let's be fair, though: you want people in government who are going to best represent you, and a majority of Americans are still religious in some way. And, sure, there are probably places in the States where people are too focused on the religion of people they're hiring or voting for, but situations like that are true in every country.
This nonsense about America hating you, never giving you a job, and never voting for you simply because you don't believe in God is simply that, however: nonsense. Countless people in this country don't believe in God, don't make a big deal about it, and go about their lives with none of this supposed persecution every day.