I am a Catholic, I will not vote for an athiest. Why? Look at what used to be known as the Soviet Union (Union of Soviet Socialist Republic). Look at the history behind Lenin. An Athiestic government killed more Catholic, Orthodox, and jewish people than Adolf Hitler, and yet, Hitler was a Catholic, educated by the Benedictine Monks in Austria. We don't want another King George III, Lenin, nor another Hitler. Athiests are more likely to shove their idealogy down our throats as the absolute, as we have seen in Soviet Russia. America has to maintain Vigil. This is one of the reasons that the federal Government has a balance of power check system in place, so that we never have a dictatorship!
Karl Marx wrote that religion is the 'opiate' of the masses, invented purely to give people something to believe in, and therefore make control easier. To cut a long story short, religion would not be necessary in a communist society, because people would not need to find solace in a God in order to endure their own subjugation.
I'd also like to point out that it was, in fact, Stalin (not Lenin) who was responsible for a greater number of deaths than Hitler. However, I would like to point out that Stalin was responsible for the deaths of his opponents, who were just as likely to be atheists as religious. Hitler was similarly responsible for the deaths of opponents of differing beliefs. [EDIT: I realise upon re-reading that this was poorly phrased. Hitler was certainly responsible for the deaths of millions of Jews. I was merely attempting to point out that he was also responsible for the deaths of people of differing beliefs purely because they opposed him.]
An atheist government would not be any more likely to shove its beliefs down our throats than a deeply religious one. In my opinion, religion and politics should remain apart. I also believe that religion and science should both be taught in schools. People should be taught all existential theories, and be allowed to choose for themselves. I dread to think that children can be taught creationism, but not the Big Bang or Darwinism in schools, but I'd also hate for kids to not learn about religion, as it played a huge role in our past, plays a huge role in our present, and is likely to play a huge role in the forseeable future.
Anyway, I'm straying from the topic here. I would certainly vote for an atheist, and I would certainly vote for any religious person. The religious beliefs of a politician do not matter to me, as long as they don't try to force them upon us through their policies. If a politician sought to remove creationism or religion from the NC, I wouldn't vote for him/her. I would also not vote for a politician who sought to have creationism be the only theory taught.
(However, if a politician sought to have both taught equally in schools, I would certainly support that. I feel people should know both sides of the argument, so that at least I can have a damn good debate about it!)