Yes, it would be unless the GOP candidate is actually working to undermine the conservative cause.
At this point, every Republican politician should be considered a potential quisling until proven otherwise. A RINO can do much more damage from the inside than any overt liberal could possibly hope to do from the outside. We are gradually seeing more and more operatives from the Trump administration out themselves. It would be much easier to point out those who weren't working against him.
In CA the GOP doesn’t even pretend to represent us.