This is a topic that has always irritated me a bit -- whether a person must believe in some god to be a moral person. Religious people like to think they have a corner on morality. They would have everyone believe that a person must be religious (and in particular, a follower of their specific religion) to be moral.
To me, that view seems to sell humans short. It says they must be threatened or ordered to be good (moral) by a god, or they will not do so. I have more faith in humanity than that. I think most humans are inherently good and moral, and will do the right thing without having to be threatened with some god's retribution. In fact, I have to wonder about the morality of those who do so only because they are afraid of some god's retribution.
I simply don't understand why anyone would need orders from some supernatural being to treat their fellow human beings kindly, decently, and honestly. In the United States there are somewhere in the neighborhood of 30 million atheists. Most of those people, just like most religious people, are decent and moral people. They deal honestly with their fellow countrymen, treat them with respect, and obey the country's laws. If they didn't, we would live in a lawless society -- because we couldn't build enough jails to hold that many people. That one fact shoots a big hole in the argument that one must believe in a god to be moral.
The two charts above show the countries where a majority think a belief in god is necessary for morality, and the countries where a majority think such a belief is not necessary to be moral. Note that the countries thinking belief in a god is necessary are those with the highest number of uneducated people and the highest rates of poverty. And the countries that think a belief in god is not necessary are largely the countries that are the richest and the most educated.
The biggest exception to this rule is the United States, where a majority (53%) think morality requires a belief in god -- even though it is a rich country and pretty highly educated (at least on a high school level). I believe much of this is due to a willful ignorance among people who take pride in denying science and education. But even in the United States, note that the higher the level of education the less that this belief that a god is necessary exists (37% with a college degree say belief in a god is necessary while 59% without a college degree believe that).
The truth is that a person who doesn't believe in a god can be a decent and moral person, and a religious person can be an evil and immoral person. It depends far more on what kind of human a person wants to be than on whether they believe in a supernatural being.