Cite as: 572 U. S. ____ (2014) 25 Opinion of ROBERTS, C. J. so. See 2 U. S. C. §441a(a)(5) (“all contributions made by political committees established or financed or maintained or controlled by . . . any other person, or by any group of such persons, shall be considered to have been made by a single political committee”). Moreover, if 100 PACs were to contribute to Smith and few other candidates, and if specific individuals like our ardent Smith supporter were to contribute to each, the FEC could weigh those “circumstantial factors” to determine whether to deem the PACs affiliated. 11 CFR §100.5(g)(4)(ii). The FEC’s analysis could take account of a “common or overlapping membership” and “similar patterns of contributions or contributors,” among other considerations. §§100.5(g)(4)(ii)(D), (J). The FEC has in the past initiated enforcement proceedings against contributors with such suspicious patterns of PAC donations. See, e.g., Conciliation Agreement, In re Riley, Matters Under Review 4568, 4633, 4634, 4736 (FEC, Dec. 19, 2001). On a more basic level, it is hard to believe that a rational actor would engage in such machinations. In the example described, a dedicated donor spent $500,000—donating the full $5,000 to 100 different PACs—to add just $26,000 to Smith’s campaign coffers. That same donor, meanwhile, could have spent unlimited funds on independent expenditures on behalf of Smith. See Buckley, 424 U. S., at 44–51. Indeed, he could have spent his entire $500,000 advocating for Smith, without the risk that his selected PACs would choose not to give to Smith, or that he would have to share credit with other contributors to the PACs. We have said in the context of independent expenditures that “ ‘[t]he absence of prearrangement and coordination of an expenditure with the candidate or his agent . . . undermines the value of the expenditure to the candidate.’ ” Citizens United, 558 U. S., at 357 (quoting Buckley, supra, at 47). But probably not by 95 percent. And at least from