10 FEDERAL ELECTION COMM’N v. TED CRUZ FOR SENATE Opinion of the Court Corp. v. Cuno, 547 U. S. 332, 353, n. 5 (2006). Here, however, appellees seek to challenge the one Government action that causes their harm: the FEC’s threatened enforcement of the loan-repayment limitation, through its implementing regulation. In doing so, they may raise constitutional claims against Section 304, the statutory provision that, through the agency’s regulation, is being enforced. Cf. Collins, 594 U. S., at ___–___ (slip op., at 18–19). Even on the Government’s version of the facts, then, we are satisfied that appellees have standing to challenge the threatened enforcement of Section 304. And because they are challenging “the constitutionality of [a] provision of [BCRA],” §403(a), jurisdiction was proper in the three-judge District Court. We thus proceed to the merits. III A The First Amendment “has its fullest and most urgent application precisely to the conduct of campaigns for political office.” Monitor Patriot Co. v. Roy, 401 U. S. 265, 272 (1971). It safeguards the ability of a candidate to use personal funds to finance campaign speech, protecting his freedom “to speak without legislative limit on behalf of his own candidacy.” Buckley, 424 U. S., at 54. This broad protection, we have explained, “reflects our profound national commitment to the principle that debate on public issues should be uninhibited, robust, and wide-open.” Id., at 14 (internal quotation marks omitted). The Government seems to agree with appellees that the loan-repayment limitation abridges First Amendment rights, at least to some extent, see Brief for Appellant 27– 32, and we reach the same conclusion. This provision, by design and effect, burdens candidates who wish to make expenditures on behalf of their own candidacy through personal loans. See 52 U. S. C. §30101(9)(A)(i) (defining “expenditure” to include loans); see also Buckley, 424 U. S., at