A new poll finds Hillary ClintonHillary Diane Rodham ClintonO’Malley tells Dems not to fear Trump FBI informant gathered years of evidence on Russian push for US nuclear fuel deals, including Uranium One, memos show Pelosi blasts California Republicans for supporting tax bill MORE more trusted than congressional Republicans over the Benghazi, Libya, controversy, as GOP lawmakers continue to probe the deadly attack on the U.S. Consulate.

Democratic firm Public Policy Polling found that 49 percent of respondents trust former Secretary of State Clinton, while 39 percent trust congressional Republicans more on the issue.

The survey was conducted from May 10-12, at the end of a week during which congressional Republicans held hearings and hammered the administration’s response to the terrorist attack, which left four Americans dead.

Sen. Lindsey GrahamLindsey Olin GrahamAlabama election has GOP racing against the clock Graham on Moore: 'We are about to give away a seat' key to Trump's agenda Tax plans show Congress putting donors over voters MORE (R-S.C.) this week suggested Clinton be subpoenaed to testify on the attack, and Rep. Darrell Issa (R-Calif.), chairman of the House Oversight Committee, said that responsibility for the attacks lies, if not with Clinton, than with "somebody close" to her.

Many Republicans see the Benghazi attack as a possible early line of offense with which to hammer Clinton ahead of her possible run for president in 2016. And two of her potential Republican opponents — Sens. Marco RubioMarco Antonio RubioCongress faces growing health care crisis in Puerto Rico The Hill's 12:30 Report Colbert mocks Trump for sipping water during speech on Asia trip MORE (R-Fla.) and Rand PaulRandal (Rand) Howard PaulCongress must end American support for Saudi war in Yemen Black men get longer prison sentences than white men for same crimes: study Sarah Palin on sexual harassment: 'People know I'm probably packing' so they 'don't mess with me' MORE (R-Ky.) — penned op-eds criticizing the administration's response last week.

Paul was particularly forceful in his op-ed, writing that: "The new evidence we have today — and that continues to mount — suggests that at the very least, Mrs. Clinton should never hold high office again."

But the new poll indicates the issue is not yet catching on with voters. A majority, by a 56-38 split said passing immigration reform was more important than investigating Benghazi. And a majority said passing a bill that requires background checks for gun purchases should be a priority over Benghazi by 52-43 percent.

Sixty-five percent of respondents said they didn't think Benghazi was the biggest political scandal in American history.

And despite GOP attacks, more than half of respondents still view Clinton favorably, by 52-44 percent. More than half of respondents, though, view congressional Republicans unfavorably, at 36-57.

The survey was conducted among 576 voters nationwide and has a 4-point margin of error.