Trump is winning as many in opposition are obsessed with him. He’s living rent free in their heads. It makes them irrational and in turn they do stupid things, which Trump then exploits.
Yesterday was not a good day for Trump from a PR perspective. But as an electoral issue it does not move the needle one inch. Supporters of Trump will continue to support him and opponents will continue to oppose him.
What is going to hurt the anti-Trump crowd is their incessant yammering about it. It’ll become a daily reminder to Trump voters that the rules are being unfairly applied (Obama’s alleged campaign violations resulted in a mere $350k civil fine). This will harden their resolve and reinforce why they need to get out to vote. And they’ll do it, which is contrary to most off election years.
If the anti-Trump crowd was smart, they’d cluck disapprovingly for a brief moment and then move on to some policy issue. They can’t do it. They have to make it about Trump, personally, and that means they’ll probably lose when they should win, just like 2016.