The recent Religious News Service analysis piece "Non-religious voters present a puzzle for political parties" makes a few decent point but does overlook a few key points. I won't pretend to speak for all atheists let alone all of the "nones" but there does seem to be one political element that many of us can agree on; Separation of Church and State.
"The nones are also a difficult group for politicians to define and woo, said Dan Cox, research director at the Public Religion Research Institute. They’re not cohesive, in that they include atheists and agnostics but also believers unattached to religious institutions. And unlike the pursuit of an actual religious group, it’s not so clear how to connect with the millions of people defined by their lack of religious connections."
It is true that we are one of the most diverse demographics around. However, I have yet to come across any that fall under the "nones" label that particularly like being told by others what and how we should think. Most also seem to distrust or dislike religion being foisted on the rest of us. Seems to me that if a politician wants to court us as a group they would have to make it clear they will not use their own or accept others attempts at imposing religious views on the rest of us. That would mean clearly and consistently supporting the Separation of Church and State. That doesn't seem too "difficult" to figure to me.