Atheists actually successfully gaining public office in the US are rare in any state. It's easier if you at least pay lip service to the idea of Christianity than hold any alternative religious belief, from Judaism to Islam to Hinduism to atheism.
This is the thing that fascinates me, when comparing American secularism with Australian secularism.
The people who wrote the Australian Constitution in the 1890s were obviously influenced by the British system of government (which had already been adopted in the colonies - now states). But they also consciously copied aspects of the American Constitution. So our two houses of Parliament are the House of Representatives and the Senate, with seats in the House allocated in proportion to population and seats in the Senate allocated at a fixed number per state (currently 12 per state and 2 per territory). But the constitution also prevents Parliament from establishing a state religion, prevents the imposition of religious observances, and prohibits limits on the free exercise of religion.
So the first Australian-born Governor General (after a series of British appointees) was the Jewish Sir Isaac Isaacs, our current Prime Minister is an unmarried atheist woman, and the current Finance Minister is an openly lesbian mother.
ETA1: I don't know how many of you saw the story which popped up shortly after Obama won the last election: a young woman, unhappy with the election result, announced on Twitter that she was moving to Australia because "their president is a Christian and actually supports what he says". So she managed to get a trifecta of wrong, which mightily amused a lot of Australians.
ETA2: I know that when trying to explain why Americans are so religious when compared with people from countries in northern Europe, a lot of people point to the fact that the northern European countries have state religions while the USA doesn't. They propose that the American lack of government support for, or endorsement of, one particular church leads to a religious free market which forces churches to compete with each other to attract congregations.
But this argument doesn't explain Australia - like the USA we don't have a state church, but like northern Europeans we just aren't very religious. I suspect the explanation lies in the fact that in Australia and in northern European countries governments provide a generous social security system, thus greatly reducing a major reason churches exist - to provide charity.
Certainly churches dominate the charity sector, but to a large extent their role is limited to people on the margins of society. But because so much charity comes from the government in the first place, when governments cut back on social welfare and churches pick up the slack, I don't get the impression that church attendance increases. In other words, churches aren't really able to turn recipients of their charity into members of their church.