The relationship between House Select Committee on Benghazi Chair Trey Gowdy (S.C.) and ranking Democrat Elijah Cummings (Md.) has deteriorated as Hillary Clinton prepares to testify before the panel on Oct. 22.

House Democrats are turning up the pressure on Republicans over their handling of the Benghazi committee ahead of Hillary Rodham Clinton’s high-profile testimony later this month, releasing interview transcripts on their own and considering forcing lawmakers to vote on the panel’s existence.

On Monday, Democrats on the special committee released portions of interview transcripts from Clinton’s chief of staff while she was secretary of state, accusing GOP leaders of selective leaks designed for political gain. The excerpts were more favorable to the Democratic presidential front-runner’s side of the story about the September 2012 attacks on a U.S. diplomatic outpost and a CIA annex in Benghazi, Libya. Democrats gave Rep. Trey Gowdy (R-S.C.), the committee chairman, five days to respond to their accusations. Otherwise, they planned to release the entire transcript.

Additionally, Democrats are considering their next steps to highlight House Majority Leader Kevin McCarthy’s recent comments bragging that the committee’s work had wounded Clinton’s presidential campaign, according to lawmakers and aides. One option would be to file an ethics complaint alleging that the Gowdy panel’s taxpayer-funded work was a misappropriation because it is essentially political in nature.

[Dems pile on after McCarthy comments on Benghazi panel]

Democrats are also considering having a rank-and-file colleague file a privileged resolution that could call for a rebuke of McCarthy’s comments or even a disbanding of the Benghazi panel. Such a move would force GOP lawmakers to vote multiple times this month on the California Republican’s standing, given his likely succession of Rep. John A. Boehner (R-Ohio) as House speaker.

Officially, top Democrats are focusing their effort on how the committee’s original mission of examining the terrorist attacks that killed an ambassador, a foreign service officer and two intelligence operatives have morphed into a probe of Clinton’s e-mail habits. “The families begged us — begged — not to make this a political football,” Rep. Elijah Cummings (Md.), the ranking Democrat on the panel, said of the Benghazi victims’ family members.

Early on, he and Gowdy worked collaboratively, but that has since changed. “We have veered so far from that, it’s incredible,” he said in an interview Monday.

Gowdy has an entirely different view of relations on the panel. “I know it’s not helpful for him to concede that, but I’ve never had a cross word with Mr. Cummings about anything,” he said Monday, adding that the two speak regularly.

The aggressive Democratic counteroffensive echoes Cummings’s actions during an investigation led by Rep. Darrell Issa (R-Calif.) into former IRS official Lois Lerner, a central figure in a scandal involving the targeting of conservative nonprofit groups. In June 2013, Cummings released a full interview transcript with an IRS manger in Cincinnati that he said “debunks conspiracy theories” about the controversy.

In her weekly news conference Thursday, House Minority Leader Nancy Pelosi (D-Calif.) signaled that Democrats are considering their next steps on Benghazi, including a potential ethics filing. “One of the things that you have to be very specific about is that none of your taxpayer dollars are used for any political purpose,” Pelosi said. “This could be an ethical issue in the House.”

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With Clinton running for president, and her hearing before the panel coming up on Oct. 22, the stakes couldn’t be higher — for both sides.

By Democrats’ account, Gowdy and Cummings communicated fairly well when the Benghazi committee was created in spring 2014. There were some early annoyances for the minority, after Democrats say they were excluded from several witness interviews and asked for a set of rules to govern the panel to no avail. But in general, relations between the two sides proceeded in typical committee fashion.

In an example of their early cooperation, Gowdy asked Cummings to reach out to Clinton in late 2014 about testifying before the committee. Clinton accepted after Cummings’s request. But by the beginning of March, according to Democrats, a seismic shift had taken place: the New York Times revealed that Clinton used a private e-mail server as secretary of state, a story that Democrats believe began with a leak from a Republican on the Benghazi panel.

First, Republicans abandoned plans to hold a series of 11 hearings in 2015 involving eyewitnesses to the attacks and top defense and intelligence officials who could provide context. Former defense secretaries Robert Gates and Leon Panetta were both listed on the schedule, along with former CIA deputy director Michael Morell and former U.N. ambassador Susan Rice.

“Suddenly all of that was thrown out the window. We did none of that — zilch,” Cummings said Monday.

According to senior Democratic aides, the focus shifted to Clinton and her e-mail practices, as well as senior staffers who did not have much to do with the response to the attacks.

One Clinton confidant who came before the committee was Sidney Blumenthal. Democrats were outraged when Blumenthal was suddenly served with a subpoena by two armed U.S. marshals at his home near the Naval Observatory, instead of being offered a voluntary interview in a letter, like other witnesses.

Blumenthal wasn’t home when the subpoena arrived, so federal marshals served the notice to Blumenthal’s wife.

During his deposition, Blumenthal was asked more than 200 questions related to the Clintons, significantly more than about Benghazi. A source who was in the room said the first time the word “Benghazi” was uttered in a question to Blumenthal was at 6:30 p.m. The deposition began at 10:30 a.m.

The transcript is not public because, under House rules, a panel’s chairman must assent to the full text being released or the whole committee must vote in favor of the move. Democrats speculated that Republicans chose to subpoena Blumenthal specifically because it would keep the content of their interview private.

In an interview Monday, Gowdy disputed every claim from Democrats, from the idea that his panel leaked evidence of Clinton’s private e-mail server to the New York Times, to the suggestion that Democrats were unfairly excluded from witness interviews, to the notion that the change in hearing strategy was designed to target Clinton, to the claim that the word “Benghazi” was not used in a question to Blumenthal until 6:30 p.m.

“I will be honest with you. Had I not been 100 percent sure that I have been on the committee since its inception, I would not recognize about half of these comments,” the former prosecutor said during a lengthy phone interview.

In Gowdy’s telling, Democrats are inventing or exaggerating facts to support the idea that the Republican is going after Clinton. Among his rebuttals, the chairman says the panel subpoenaed Blumenthal because they called him twice and he never responded.

The GOP hearing strategy shifted, Gowdy said, after Democrats used one public hearing to “do nothing but criticize process, rules and procedure,” leading him to believe that private interviews would be more productive.

The Benghazi committee has not yet interviewed Gates, Panetta and Rice because it does not yet have all their e-mails, Gowdy said.

And any change in relationships with Democrats started last fall, he said. “I got a seven-page letter detailing a list of grievances, both real and perceived…. They said, ‘We need you to narrow the parameters of the investigation. We need you to tell us which issues are still existing and which are not.’ I wheeled around as soon as I got it and I called [Cummings] on his cellphone. And I said: ‘Where is this coming from?'”

Gowdy cited instances when he was solicitous toward Democrats, from using Skype to include absent members in events to rescheduling Blumenthal’s deposition in order to accommodate a scheduling conflict for his lawyer.

“I was warned that this day would come,” Gowdy said gloomily. “I was warned by almost everybody that this period of detente would end, and that everybody getting along is not in their best interest. That is not the narrative [Democrats] need, so it changed.”

Democrats, meanwhile, say the GOP’s poor treatment of Blumenthal poisoned the well between the two sides, and the situation was exacerbated by a number of partial Republican leaks to the press.

In one case, Politico cited a GOP source to report that Cheryl Mills, Clinton’s chief of staff at the State Department, reviewed and suggested changes for a report on what happened in Benghazi by the department’s Accountability Review Board. The source told Politico that Mills’s review “call[s] into question the ‘independence'” of the report’s conclusion, a remark that caused a brief flurry of negative stories on the right.

Democrats, pushing back, said Mills’s review was already known and its relevance had been debunked two years earlier.

These kinds of leaks, Democrats wrote Monday to Gowdy, are part of their rationale for releasing the complete Mills interview transcript after five days.

[Top Clinton aide testifies on Capitol Hill]