The offloading of expenses on the state PACs also allows Mr. Romney’s federal PAC to be more generous with the money it distributes to federal candidates, who might be counted on for favors down the road.

Mr. Romney’s committees in the three states that do not restrict donations to these kinds of organizations, essentially gives him a flexible pot of “soft money” — or unregulated contributions — before he formally decides to run and becomes subject to strict federal limits on political donations.

These PACs, wrote Luo, “must be careful not to cross over into actually footing the bill for a presidential candidacy”—against the law!— a line which he says that Romney and others are “testing.” And why not? The FEC, Luo wrote, “tends to give [PACs] the benefit of the doubt on these kinds of questions.” Not to mention that the six-member FEC—politically deadlocked with three Republicans and three Democrats—has been, as described in a recent Daily Beast column, unusually “quiet” during a time of record campaign spending.

Liz Cox Barrett is a writer at CJR.