U.S. House Democratic members, including, from left, Rep. Terri Sewell (D-Ala.), Rep. John Lewis (D-Ga.), Rep. Andre Carson (D-Ind.), House Minority Leader Rep. Nancy Pelosi (D-Calif.), Rep. George Meeks (D-N.Y.), Rep. Bobby Rush (D-Ill.), and Rep. Luis Gutierrez (D-Ill.), participate in a walkout in protest of a vote on holding Attorney General Eric H. Holder in contempt of Congress. (Alex Wong/Getty Images)

When the House voted Thursday to hold Attorney General Eric H. Holder Jr. in contempt of Congress, more than 100 Democrats walked out, denouncing the vote as a political sham.

But they left behind a group of 17 Democrats who face some of the toughest reelection contests in the nation, and that group joined Republicans in rebuking Holder. That solid bloc of Democratic support for the contempt motion against an attorney general appointed by a Democratic president was a testament to the GOP’s ability to make Holder radioactive in some key swing districts and to the enduring political influence of the National Rifle Association in Washington.

Despite the vote,the Justice Department told House Speaker John A. Boehner (R-Ohio) on Friday that Holder’s decision to withhold some information from an ongoing congressional probe into Operation “Fast and Furious” didn’t constitute a crime and would not be prosecuted.

Republicans expect the vote to energize some of their most loyal supporters. But for the Democrats who voted with them, it was a chance to demonstrate independence from the party leadership and to keep the NRA attack ads at bay.

“They can use this as a stark reminder that they did not follow their party leader out the door,” said analyst Stuart Rothenberg of the nonpartisan Rothenberg Political Report. “These Democrats are trying to carve out records to let them prove their independence.”

But also, the NRA announced last week that it would include the lawmakers on its closely watched legislative score card. This week, the group turned over the homepage on its Web site to a graphic calling for NRA members to pressure lawmakers to vote for contempt.

“In my district, I hear a lot about Fast and Furious. It’s in the public discourse,” said Rep. Jason Altmire (D-Pa.), who represents a conservative district and supported contempt.

His own vote, he said, was motivated by a desire to see Holder release documents requested by Congress. But he said the NRA has successfully raised the visibility of the gun-running operation.

Republicans pursued contempt charges against Holder after the Obama administration withheld documents demanded by lawmakers as part of an investigation into Fast and Furious, a flawed federal program run by the Bureau of Alcohol, Tobacco, Firearms and Explosives from 2009 to 2011.

Several Democrats who backed the resolution said they voted with Republicans because they believed Holder was thumbing his nose at the House’s oversight responsibility. “I feel Congress has a constitutional responsibility to exercise effective oversight regardless of which administration,” said Rep. Nick J. Rahall II (W.Va.), who stood quietly in a dark corner of the House floor Thursday as most of his Democratic colleagues walked out. “If there is nothing incriminating in those documents, I see no reason why they should not have been turned over.”

Rep. Leonard L. Boswell (Iowa), facing one of the toughest reelection contests this year, agreed that Holder should hand over the documents: “Just give it to them. Back the truck up and unload it.”

But lawmakers of both parties faced intense pressure to vote for contempt from the NRA, which has vilified Holder and demanded congressional action over Fast and Furious. The NRA has argued that ATF allowed guns onto the street to boost Mexican drug violence to help build the case for further strictures on American gun sales.

“They demonized gun owners and gun retailers, and tried to blame Americans for [the] problem, for a deadly and sad problem that’s rooted in Mexico,” said NRA spokesman Andrew Arulanandam.

In the coming days, House Republicans plan to refer their criminal contempt charge against Holder to Ronald C. Machen, the U.S. attorney for the District of Columbia.

But in a letter sent to Boehner on Friday explaining the Justice Department’s decision, Deputy Attorney General James Cole cited a Reagan-era legal analysis that said U.S. attorneys are not required to prosecute congressional contempt charges if the individual was carrying out a president’s instructions to invoke executive privilege.

House Oversight and Government Reform Committee Chairman Darrell Issa (R-Calif.) disputed Cole’s decision, saying Machen should have no difficulty prosecuting Holder because he is already leading an investigation into the possible leak of classified information by Obama administration officials to reporters.

Earlier this year, Altmire lost in a primary election to Rep. Mark Critz (D-Pa.), after the two incumbents’ districts were merged in redistricting. Critz, facing a tough Republican challenge, also voted for the contempt resolution.

“The gun guys are really [angry],” said Rep. Steven C. LaTourette (Ohio), one of two Republicans who voted with Democrats to oppose criminal contempt.

He said he explained to constituents that he supported a second resolution Thursday to allow the House to initiate civil proceedings to force the attorney general to turn over records.

“Some of them calmed down,” he said. “And some are convinced I’m a RINO pinkie, and I won’t get them back no matter what I do.”

Of the 17 Democrats, all but one had previously received NRA endorsements, highly coveted by Democrats running in conservative districts.

Arulanandam said it is too early to say whether lawmakers who opposed contempt might lose their endorsement. But, he added: “We said we would support this vote and this vote counted. We meant it, and it will.”

Staff writer Sari Horwitz contributed to this report.