Do Atheists become Liberal because they have no Religion?

No,

It's because they have a brain.

The only requirement for atheism is lack of belief in a god or gods. Atheism is independent of political affiliation. Most atheists are liberal, although a fair number are libertarian. Conservative atheists are not unheard of although they are rare.

Also, even in 2013, it is almost impossible to get elected to office in America as an atheist.

So less then 5% of the population are responsible for every crappy politician in the country?

Maybe you should think a little bit before posting a question as dumb as this

And take a math class

According to Gallup(http://www.gallup.com/poll/159548/identify-christi... 77% of Americans call themselves christian while people who identify as Atheist are 4% of the population.

If we have whack-job laws and politicians, guess who is voting them in?

Yes another benefit of being free from primitive superstition. Although many Atheists are conservative so it's not universally true

Ever heard of the Christian Coalition? Most if not all presidents have been theists or a part of a religion. Do your homework, think critically before you ask dumb questions.

More intelligent people usually tend to be liberal and less religious.

I'm Atheist and dont consider myself liberal. I just believe that everyone should have the same rights.

No. I became a liberal because I have some humanity in me.

I became liberal when I was a Christian. Jesus said to help the less fortunate.

You don't need to be an atheist to be a Liberal. Why would you even suggest such a thing?