Anti-vax lunacy trickles through both parties, and gets little mainstream traction (although that may change with Trump injecting oxygen into the movement). But if you're running as a pro-science Democrat who is
not an anti-GMO bandwagoneer, you will generally
not find yourself blackballed by the party or opposed on your flank by billionaire string-pullers obsessed with purity tests on this issue. The Democratic party does not have the same ideology enforcement infrastructure that so tightly binds the Republicans; that's a strength if you think monocultures are pathological, but a weakness if you're looking for lockstep execution of some received ideology.
Accordingly, if a Democrat is in power and the findings of a science-based agency contradict some policy desire, they would sigh and fret and perhaps try to initiate other studies to see if there's any other way to align their policy goals with reality. But you would not see scientists and entire agencies of thousands of workers gagged, studies removed, data destroyed, conclusions banned. You would not see them scrambling to align reality with their goals and literally banning facts. It's little exaggeration to say the Trump administration is now engaged in book-burning.
Whatever the flaws of the Democratic party, what's "in vogue" with the party is an epiphenomenon, not the driver. If you want to run as a pro-science non-religious Republican, you are desperately needed for the health of the US political system -- but you will almost certainly be structurally unable to do so.