Trump self financed a lot of his campaign. It is still legal to spend your own money to payoff tramps.
It is legal to contribute an unlimited amount to your own campaign, as long as it is disclosed. (See examples like Sen. Elect Rick Scott, or Gov. Elect Pritzker in IL.) What you can’t do is contribute $ or services (in kind contributions) that are not disclosed. And if you are an individual contributor who is not the candidate, you have modest annual limits on how much you can contribute. If you are a corporation or a non-US citizen, you cannot contribute anything to a candidate’s campaign. in other words - shouldn’t Stormy Daniels have to report a contribution to Hillary ‘16?
I’m not sure how I feel about Trump’s possible culpability here. If and when necessary he can pattern a defense off the John Edwards prosecution. It worked for him.
What does bother me is the unequal application of the law. If, say there was a woman who had some affair with Trump 10 years earlier and never pursued a cause of action (for harassment, for defamation, etc.) stemming from the past behavior, and only chooses to raise the threat of doing so when he becomes a candidate - isn’t that threat in effect a contribution in-kind to the Clinton campaign? I mean, that is what they are leveraging, their ability to do damage to Trump, which is in a practical zero-sum game like the race between the two major party candidates, effectively a contribution to Clinton.
It is a giant stretch of the law to presume that money paid to keep an alleged affair from the public (and maybe one's spouse) is automatically a campaign expenditure. Campaign or not people pay money to keep other people quiet.
As one example, I'll bet that most if not all of the settlements that Congressmen and Senators made regarding allegations of sexual harassment include a confidentiality clause. And it seems highly likely that public disclosure of a Congressman or Senators sexual escapades would influence their next election under Mueller's theory. So when do all those Reps and Senators get indicted? They didn't use their own money, they used the taxpayers money on what Mueller and the media now insist is a campaign expense. Since when would that be legal?
If Trump's expenditure to keep Stormy Daniela silent was a campaign expenditure, then so were all the payments made by the government to settle claims of sexual harassment against Reps. and Senators.