This very question being asked, and the rather emphatic answers given, remind me of a quote (rather prophetic, in my own opinion) of George Washington:
“However [political parties] may now and then answer popular ends, they are likely in the course of time and things, to become potent engines, by which cunning, ambitious, and unprincipled men will be enabled to subvert the power of the people and to usurp for themselves the reins of government, destroying afterwards the very engines which have lifted them to unjust dominion.”
When political parties became “slates,” “platforms,” and “blocks,” they ceased to worth the one value they had of limiting candidates. A representative democracy works as a democracy only when those representatives represent their constituents, not their party. That is why our government is so erratic and ineffective, swinging back and forth with every election and lacking a single direction.
I do not know if this happens everywhere, but in my locality, all elected officials run under a party platform, 95% Republican, because of this limited mentality that party trumps people. One cannot run, or vote, for another in a different primary. Thus, parties are no longer just a set of ideological groups, but an engine of power. The disparaging term “RINO” ignores this problem. With a dash of totalitarian control, and a hint of bigotry, many have defined the party as an absolute block. Yet even party platforms are not unanimous. Neither should one be required to have the exact opinions of others to have any chance to be elected.
So I do have a sympathy for Democrats who face the reverse problem and know of at least one pro-life Democrat who lives in such an area.