Some of the nation’s biggest corporations donated more than a million dollars to launch a Republican nonprofit that went on to play a key role in recent political fights.

Like the nonprofit groups that poured money into last year’s elections, the decade-old State Government Leadership Foundation has been able to keep the identities of its funders secret. Until now.

A records request by ProPublica to the IRS turned up a list of the original funders of the group: Exxon, Pfizer, Time Warner, and other corporations put up at least 85 percent of the $1.3 million the foundation raised in the first year and a half of its existence, starting in 2003.

The donor list is stamped ‘not for public disclosure,