A smart WSJ follow-up story about McCutcheon suggests that Republicans—no names yet—want a plaintiff—no name yet—to take the case for money in campaigns even further.

Because the recent plaintiffs hadn't challenged the base limits on political contributions, "we see no need in this case to revisit Buckley's distinction between contributions and expenditures," Chief Justice Roberts wrote.

Republican and conservative lawyers interpreted those remarks to mean the court would be ripe to strike down other campaign-finance restrictions. The decision "seems to crack the door open" to a legal challenge aimed at allowing political parties to raise unlimited contributions, said William McGinley, a Republican campaign-finance lawyer with the Washington law and lobbying firm Patton Boggs.

Now, as the paper points out, Shaun McCutcheon was one of fewer than a thousand donors who had previously felt compelled to donate to more than nine candidates in a cycle. (My favorite genre of post-McCutcheon story is the one that asks rich people if they really want to blow through the checkbooks like this. "We were joking around with the partners today: Guess my kids are going to community college," said one lobbyist to Nick Confessore. "There is going to be no end in sight.") McCutcheon's an affable guy; his lawyer, Dan Backer, is an ambitious operative. They were ready for whatever opprobrium they got.

So who's going to test the limits with a lawsuit? Surely the current PR campaign to defend the Kochs and other donors from liberal mobs are going to make it easier to find someone. In Commentary, Seth Mandel dings me for criticizing Charles Koch's WSJ column about the attacks on his free-speech rights and his company. "Koch is speaking up because he has been the target of constant attacks from the United States Senate majority leader from the chamber floor," writes Mandel. "Harry Reid actually worked an attack on the Kochs into his reaction to yesterday’s Supreme Court ruling on campaign finance, as he does for almost anything."

This comes from a growing sentiment on the right that private citizens should not be singled out and criticized by politicians—by the people who theoretically control the means to prosecute them or investigate them. Mitch McConnell conveyed that even as he snapped at Reid by criticizing the donations given by Tom Steyer. "It strikes me as curious that if we are going to demonize people for exercising their constitutional rights to go out and speak and participate in the political process," he said, "we would just pick out the people that are opposed to us and leave out the people who are in favor of us." Donors can fund ads that attack politicians; to criticize them is to privilege the politician at the expense of free speech. That's the argument, and the one that will encourage a donor to test, with the hope of obliterating, all caps on donations.