Looks like the Democrats continue to be the party of inclusion, while the Republicans continue to the the party of exclusion.
If people who claim no religious affiliation are the largest and fasted growing 'religious' group in the U.S., then this may be a smart political strategy. I don't think most of the 'non's' the Democrats are targeting with this policy are actually non-religious. Instead, most probably are Christian but do not affiliate with any particular denomination because of the exclusionary tendencies traditional Christian denominations display.
Being an atheist, this new strategy still does not mean I'm voting Democrat. I still want to see who they nominate, but the prospects for be voting for the Democrat candidate are looking slimmer than ever. I voted for Johnson in the 2016 election because I didn't like Trump (still don't) and refused to vote for Clinton.