Also, while it is true that there are more LWers that are atheist than theist, male than female, white than other races, etc, it is at the same time very unlikely that most LWers have all those characteristics.

Given that we are 86.2% male cisgender, 84.3% caucasion (non-hispanic), and 83.3% atheist (spiritual or not) that means a minimum of 53% of LWers are all three; probably the actual number is over 60%.

In answer to the parent, atheism in America may have started becoming a more liberal pursuit somewhere around 30 years ago when the Republican party started being substantially more religious and dismissive of atheism and science.