Chris Bowers has an excellent post up, which I fully agree with:

This is not a negotiable position. If the Democratic Party does not
nominate the candidate for POTUS that the majority (or plurality) of
its participants in primaries and caucuses want it to nominate, then I
will quit the Democratic Party.

They really need to listen to the people and not the beltway on this election. I have made it known to a few people that I will also be doing the same.