President Obama should waste no more time and sign an executive order requiring government contractors to disclose any checks they write to the newly legal troughs of secret campaign donations. House Republicans, who in the past loudly supported such transparency, are holding hearings to push the absurd claim that Mr. Obama is aiming to violate donors’ free speech.

Government contractors are already required to disclose their spending through political action committees. The order would extend that requirement, and transparency, to money going to new groups shrouding donors and their true political goals.

Voters certainly have a right to know which companies doing business with the federal government — and paid with tax dollars — are also trying to curry favor with politicians.

If Mr. Obama fails to issue the contractors’ order, he will underline the hypocrisy of his own campaign supporters’ decision to go all out for their piece of the secret money torrent. Representative Steny Hoyer, the Democratic whip, certainly didn’t help when he recently questioned the propriety of the disclosure order.