The GOP is a social hierarchy while the Democratic Party is a social coalition. Thus with rare outliers such as Obama's endorsement of marriage equality, Democratic aligned voters are much less likely to go along with leadership and endorsement cues per se. Republicans tend to quickly and strongly align with leadership signals; Democrats basically don't care about what Biden or whoever has to say.
The GOP is a social hierarchy while the Democratic Party is a social coalition. Thus with rare outliers such as Obama's endorsement of marriage equality, Democratic aligned voters are much less likely to go along with leadership and endorsement cues per se. Republicans tend to quickly and strongly align with leadership signals; Democrats basically don't care about what Biden or whoever has to say.