That's what the Court did today, by a 5-4 vote, in McCutcheon v. Federal Election Commission. The main opinion was written by Chief Justice Roberts. Justice Thomas, concurring in the judgment, would have gone further and overruled Buckley v. Valeo, which, among other things, upheld certain individual limits on contributions to particular candidates. No surprise there. He has urged that Buckley be ditched before. The aggregate limits at issue in McCutcheon limit (or, I guess I should say now, used to limit) how much money a donor may contribute in total to all candidates or political committees in a particular election cycle. See 2 U.S.C. § 441a(a)(3). Justice Breyer wrote the dissenting opinion.