It seems a certainty that up to a dozen Democrats will defect from their party and vote Eric Holder in contempt of Congress.

House Speaker John Boehner is pressing ahead with a floor vote that is almost certain to pass, with the majority Republicans expected to get the backing of some Democrats. At least five Democrats so far have said they plan to vote to hold Holder in contempt, and sources tell Fox News as many as 11 appear ready to break ranks.

Those Democrats are largely conservative-leaning lawmakers facing perilous political circumstances in their home districts. But regardless of motive, their support only increases the odds that the nation's top law enforcement official will be held in contempt of Congress come Thursday.

The vote against a key Obama administration official comes on the same day the Supreme Court is due to announce its decision on the constitutionality of President Obama's health care law, the administration's key domestic agenda achievement. The contempt vote, however, is expected to take place sometime in the afternoon, several hours after the Supreme Court decision.

If the contempt measure passes, it would touch off a whole new legal process -- in which a U.S. attorney would be called upon to convene a grand jury to consider the allegations and whether to indict, though with Holder at the helm it's unclear how that would play out. 

The two sides also will likely continue to battle over the documents at the heart of the dispute as Obama tries to lock them down by claiming executive privilege. 

It looks like Holder's contempt citation will draw far more bi-partisan support than Obamacare did in 2010.

Meanwhile, the Congressional Black Caucus will stage a routine walk out during the vote, thus proving that their kind of activism has gotten so boring, nobody cares what they think.

The Congressional Black Caucus plans to walk off the House floor during tomorrow's votes to hold Attorney General Holder in contempt of Congress, according to a letter being circulated among members of Congress.

"We adamantly oppose this partisan attack and refuse to participate in any vote that would tarnish the image of Congress or of an attorney general who has done nothing but work tirelessly to protect the rights of the American people. We must reflect upon why we are elected to this body and choose now to stand up for justice," the CBC members wrote in a copy of the letter obtained by POLITICO. "We call upon all members of Congress to stand with us during a press conference on the Capitol Building steps during this appalling series of votes to discuss our nation's most significant priority - creating jobs.  At this critically important time in our nation, we must work as colleagues rather than political enemies."

They must have Eric Holder confused with someone else. It is a laughable statement to make that Holder "has done nothing but work tirelessly to protect the rights of the American people."

Well..some Americans, anyway.

A vote is expected this afternoon.