I believe what had put off the largest number of Republican voters in Alabama happened well before there was a special election senate campaign
Moore had been elected as Chief Justice of the Alabama Supreme Court twice, and pulled stunts that resulted in his being removed from the court both times. That reminded older residents of how George Wallace also defied federal courts and put the state in the history books forever in very negative ways. Many voters did not want another state official carrying on that tradition and many Republican voters probably stayed home.
Why elect someone to an important statewide office when they lack the judgment and common sense to not carry out defiance of federal courts or laws when he has no chance of winning on a particular issue?
“Where Do You Go to Get Your Reputation Back?”