Rep. Darrell Issa from California said Thursday that he wants a special prosecutor called to investigate whether the White House broke the law by allegedly offering a job to a Democratic congressman to coax him out of a race against a prominent senator. 

Issa, the top Republican on the House Oversight and Government Reform Committee, said he thinks there's a "very high" chance of getting a prosecutor assigned since the allegation would constitute a crime. 

"What you have is a credible allegation by a member of Congress of a felony," Issa told Fox News. "It is a felony to offer somebody a federal job in order to get them to affect an election." 

The allegation is that the White House offered Rep. Joe Sestak, D-Pa., a job to abandon his primary challenge against Sen. Arlen Specter, D-Pa. The allegation first surfaced in an interview in February with Philadelphia television anchor Larry Kane. 

Sestak told Kane that he was offered a federal job to exit the race. When Kane asked if the White House offered the position, Sestak replied, "Yes." 

Sestak has said he's not withdrawing from the race, but has since clammed up about the incident. He declined to elaborate on the allegation in an interview with Fox News March 10. 

Meanwhile, the White House has offered little information about the conversation that may have transpired between administration officials and Sestak. After initially dodging questions on the topic for weeks, White House Press Secretary Robert Gibbs last week said he talked to "people" in the White House about the claim and that, "I'm told whatever conversations have been had are not problematic." 

He added that the incident is "in the past." 

Not for Issa. He said Thursday that the assessment from Gibbs that the alleged incident was "not problematic" is not enough to avoid more scrutiny. 

"It's very clear that a special prosecutor is statutorily and historically the right way to go," he said. "If they had any possibility of being credible in offering it, that's a felony."