Susan Walsh, Associated Press
Democratic presidential candidate Hillary Rodham Clinton listens at left as House Minority Leader Nancy Pelosi of Calif. speaks to reporters on Capitol Hill in Washington, Tuesday, July 14, 2015. Clinton, who spoke to reporters on the deal reached with Iran, attended meetings on Capitol Hill with House and Senate Democrats.

WASHINGTON — A special House committee on the 2012 Benghazi attacks has devolved from an investigation into the deaths of four Americans in Libya into a political fight over Hillary Rodham Clinton's emails and private computer server — a battle that is likely to stretch into the 2016 presidential election year.

Republicans say Clinton has only herself and the department she once ran to blame for the shift in focus amid her campaign for the Democratic presidential nomination. Clinton, who served as secretary of state in 2012 when militants attacked the U.S. mission in Benghazi, chose to use a private email server, rather than a government server — and later deleted thousands of emails she said were not related to her work.

The State Department, meanwhile, has struggled to produce a trove of emails involving Clinton and some of her key staffers. The resulting impasse has prolonged the committee's work, said Rep. Trey Gowdy, R-S.C., the chairman of the Benghazi panel.

"The reason we are having a conversation about her email arrangement is because of her unusual email arrangement with herself, and not because of anything we've done on the Benghazi committee," Gowdy, a former prosecutor, said in an interview.

Rep. Elijah Cummings of Maryland, the committee's ranking Democrat, said the panel has assumed a new purpose: "Derail Hillary Clinton's presidential efforts by any means necessary."

"Anybody can now see that's what it's all about," Cummings said in an interview. He'd like to see Clinton testify before the committee as soon as possible.

There's no such session scheduled, even though Clinton is expected on Capitol Hill Tuesday to meet with congressional Democrats.

Her campaign, meanwhile, has posted a 3,600-word fact sheet on the candidate's use of a private email server during her time at the State Department. The statement said Clinton's use of a private email account was widely known at the State Department and that department policy during her tenure permitted her to use a non-government email for work.

What's undisputed is that the select committee's work will continue into 2016, guaranteeing that Benghazi — and the deaths of four Americans, including U.S. ambassador Chris Stevens — will shadow Clinton during her second White House bid.

Clinton herself may have provided a glimpse of that future when she declared during a CNN interview last week that she "never had a subpoena" compelling the production of emails sent while she was secretary of state.

Gowdy pounced, releasing a subpoena he issued to Clinton in March to "correct the inaccuracy" of her claim. In fact, he had publicly announced delivery of the document at the time.

He didn't tell Clinton to go on TV, Gowdy said, "and I certainly didn't tell her what to say. Had she not said what she said to the CNN reporter, you would not have seen my homely self on TV."

Cummings rose to Clinton's defense, calling her statement "an honest mistake" and denouncing the GOP's release of the subpoena as a "stunt" in an ongoing "taxpayer-funded attack" on the Democratic front-runner.

Cummings and other Democrats voted against creating the panel last year, saying that at least eight previous investigations had disproved a variety of conspiracy theories about the attacks nearly three years ago. Notions that U.S. forces were ordered to "stand down" during the attacks or that Clinton played a direct role in security decisions are false, congressional investigators say.

Gowdy maintains that the committee is not concerned about conspiracies, but intent on learning the full truth about the attacks. The focus on Clinton is because, "No. 1, she was secretary of state at all relevant times. That's a pretty big fact," he said.

"I wonder if she brought her emails with her," House Speaker John Boehner told reporters Tuesday when asked about Clinton's visits with congressional Democrats.

Boehner, R-Ohio, has said House Republicans will continue to press for Clinton's emails, adding, "This is going to go on throughout the rest of this year."

"If Hillary Clinton wants the Benghazi committee to finish their work, she could help them by turning over all of her emails sooner rather than later," he said Tuesday.

Despite her claims to the contrary, Clinton has not been fully forthcoming about her emails and other important documents, Gowdy and other Republicans said.

For instance, while Clinton has said she turned over "the entire public record" of her emails, "we know that is not accurate," Gowdy said, citing at least 15 work-related emails from Clinton's private server that the State Department says it cannot find.

Republicans also are frustrated that the State Department has been slow to release emails sent by key Clinton staffers, including top aides such as Cheryl Mills, Jake Sullivan and Huma Abedin.

While Democrats accuse Gowdy of stalling a planned interview with Clinton to ensure it happens closer to the 2016 election, Gowdy said any delay is the fault of the State Department, which has failed to produce emails the committee is seeking.

"The sole person keeping me from having that conversation (with Clinton) is her successor, John Kerry," Gowdy said.

Rep. Adam Schiff, D-Calif., a member of the Benghazi committee, said the panel has become exactly what he and other Democrats feared it would be when it was created in May 2014: an ongoing, taxpayer-funded effort to diminish Clinton's presidential campaign.

"To whatever degree this was ever about Benghazi, those days are gone," Schiff said, predicting that Republicans will spend the next six months or more "going after" Clinton.

While that is to be expected from the Republican National Committee, Schiff said, "it's not OK for a taxpayer-funded committee that is supposed to be finding the truth."

Associated Press writers Ken Thomas and Alan Fram contributed to this story.

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