It has been a rough couple of days for Attorney General Eric Holder and it doesn't look to be getting any easier.
Florida Republican Sen. Marco Rubio became the sixth senator to call for Holder's resignation Thursday during a breakfast with reporters. [Romney Faces Tough Test on Immigration.]
When pressed on whether Holder should step down, Rubio said "I do, at this point, I do. We've now reached the point of no return on this issue."
The House Committee on Oversight and Government Reform voted Wednesday to hold Holder in contempt of Congress after he failed to turn over thousands of subpoenaed documents. Simultaneously, House Speaker John Boehner took an unprecedented step in announcing he would bring the contempt charge to the House floor for a vote next week.
In 1998, the same house committee voted Janet Reno in contempt of Congress, but the motion was never brought to the floor for a vote.
New York Rep. Carolyn Maloney, surprised by leadership's aggressive move, scoffed Thursday that "even Newt Gingrich wouldn't hold a contempt vote on the floor of the United States Congress."
Rubio stuck by GOP presidential nominee Mitt Romney, who has also called for Holder's resignation, saying that "I think they have been given multiple opportunities to answer really legitimate questions Congress has." [Read: Obama offers 'deferred action' to young illegal immigrants.]
Rubio, who is still upset at President Barack Obama for jumping in front of his bipartisan immigration legislation last week, also blamed the White House for once again muddling in the affairs of Congress by invoking executive privilege over the subpoenaed documents.
"Evoking executive privilege in the 11th hour [Wednesday] is probably the last straw," Rubio said. "If you refuse to provide information to allow Congress to play that [oversight] role then it really undermines the very principals of our republic and the separation of powers."
Rubio said he couldn't imagine how Holder could operate the highest judicial office in the country anymore, adding he lost "credibility" in the "Fast and Furious" scandal, a government program that allowed drug lords to buy guns in hopes that they could track them and later arrest them on arms trafficking charges.
Rubio has dismissed the accusation that the contempt vote is simply election-year theater, saying Republicans will continue to make the economy the centerpiece of the 2012 election.
"The economy will continue to be the dominant issue, but that doesn't mean we ignore other important issues," Rubio said. "I think our political process and our political leadership is capable and better be capable of handling multiple issues at a time because that is the way the world works."
Lauren Fox is a political reporter for U.S. News and World Report. E-mail her at email@example.com or follow her on Twitter @foxreports.