Top GOP oversight official Rep. Darrell Issa said in a May 9 letter that if a top Obama aide again declines to testify on a draft executive order requiring political disclosure from government contractors, Issa will be “required to consider the use of compulsory process” – a congressional subpoena.

If Issa subpoenas OMB director Jacob Lew to testify about the draft order, which Republicans warn could allow the administration to politicize the government contracting process, it would be the first time the GOP has subpoenaed the Obama White House since they obtained the authority in taking over the House in January.

A source close to Issa says he’s serious. “This will end one of three ways,” the source told The Daily Caller, “one, Lew will acquiesce and testify, two, they’ll negotiate a date in the near future when he will testify or three, they’ll subpoena him. I really think they’re serious.”

The draft executive order implements a provision in the “Disclose Act,” campaign spending legislation drafted in response to the Supreme Court’s Citizens United decision that failed in Congress when Democrats controlled both chambers.