Not when election season rolls around. Their voters vote in lockstep. Also, not when Democrat elected officials vote. They too vote in lockstep according to what their Leader orders them to do.
Yes, they bicker occasionally the rest of the time, but not when it's time to vote.
Are u forgetting the Obama/Clinton primary? But in general democrats don’t have deep ideological divides. Until the last 8ish years, this forum was an outlier in the party.