The biggest single reason Trump was elected was due to campaigning for "the wall" yet both parties ignore the voters over and over on this. Voters are pissed and I really don't understand how both parties can pretend otherwise.
They don't care. We're pissed. So what. Tough shitsky.
I have laid out the simple calculus of the ballot box:
If it's a red state/district, the voters will vote for whatever GOP candidate is fielded, barring an 11th hour pseudoscandal, and not vote at all if they don't. (Roy Moore, AL, for an example of the latter).
In heavily Democrat districts, the votes will go to the Dem, whoever it is, or they won't go at all,
If a candidate who works through the Primary process successfully is patently unacceptable to the power cartel in D.C. the synergy of an 11th hour scandal with a withdrawal of Party support will be used (along with voter fraud) to elect their opponent, if necessary, if they cannot be pushed to withdraw.
Only in districts where the ballot is close is there any contest, but regardless of who wins, they will play ball in D.C., for fun and profit, and the voters will come in last. We used to call that process of corruption 'getting Beltway Fever', but now I believe most candidates are compromised long before they are elected.
Theoretically, we can challenge candidates in primary elections, but keep in mind that requires that the Party list the candidate, at least acknowledge them. Don't have complete faith in that process, either, and keep in mind that in today's news environment, allegations of wrongdoing can be used to scuttle any campaign, following 'leaks' citing unnamed sources who wish to remain anonymous without a shred of credible evidence, and leave the candidate trying to prove a negative (logically, the most difficult position) in the public eye, taking the spotlight off of bloody murder, if need be, in the other camp to elect someone who will 'play ball'.