The National Atheist Party was founded by Troy Boyle. The idea came to him from watchinmg a Richard Dawkins interview. He began the party on Facebook.
"The party's platform was decided on by a vote — again via Facebook — and
includes hot-button issues such as gay marriage (for it) gun control (tighten
it), abortion (a woman's decision), immigration (reform it), energy (green it),
and the economy (legalize recreational drugs to create revenue and jobs)." USA Today
The fool hath said in his heart, There is no God. Psalm 14:1
While we don't want Church & state to unite-we also don't want the state to ban or harass religion. A party exclusive for the cause of atheism would do just that-ban or harass religion.