Here is a bit of an explanation from the repeal machine engineer:
A little background before getting to Candidat-A. The Repeal Machine uses a tight method to get maximum effect during each election cycle. It has two main parts:
1. Identify who are our legislative allies (green) and opponents (red)
2. Determine which races are the most closely matched (and most easily influenced)
We look for the best opportunities based primarily on these two factors. But there are also "high value" targets, such as committee chairs, committee members, majority/minority whips, etc. These are the key legislators who can prevent our bills from being voted on, so these "bill blockers" get an elevated priority when it comes to evaluating all the possible races.
It all boils down to picking races where we have the most impact. The closer the race, the greater our ability to change the outcome. (This is why primary races and special elections are so important, since they normally have low voter turnout, and often have very small margins of victory.)
The reason I say this is that producing a viable candidate who will run against a bad legislator is an "extra" activity. While it's perfectly reasonable to attempt it, and it's definitely worth doing, the Repeal Machine is focused entirely on picking the "low hanging fruit" that's within easy reach.
That said, I always encourage activists to jump in at the ground level when it comes to political candidates. This always makes sense. But the caveat is that fighting against a strong incumbent with a long-shot challenger is never the best use of campaign volunteers. That's why we choose to bypass our worst enemies when we know they are unbeatable. The Repeal Machine specializes in concentrating our energy, and then applying it against the most vulnerable targets. The primary objective is to get results on election day, so we hit hardest at the chinks in their armor.
When it comes to Candidat-A, we need to find out how strong he is, as well as who (if anyone) is running against him. Next, we find out if his challenger supports some type of adult choice on helmets. If so, the last step is to find out if the challenger has a reasonable chance of winning. Then it's a go.
If it turns out that Candidate-A looks unbeatable in the next election, we will instead pick off other nanny-crats who ARE vulnerable. But Candidat-A will stay on our radar, and when a good opportunity comes along we'll be ready to take him down. Either way, his days are numbered since his nanny-crat colleagues will be dropping like flies.