Most Americans have doubts about the Secret Service’s ability to keep presidential candidates safe after last month’s attempt on former President Donald Trump’s life, a new poll from the Associated Press-NORC Center for Public Affairs Research finds.

Only around 3 in 10 Americans are extremely or very confident that the Secret Service can keep the presidential candidates safe from violence before the election, according to the poll. The survey also found that about 7 in 10 Americans think the Secret Service bears at least a moderate amount of responsibility for the assassination attempt.

The law enforcement agency tasked with protecting presidents for more than a century is under intense scrutiny after a gunman got within 150 yards of Trump and fired several bullets from an AR-style rifle. Trump was injured in one ear but was millimeters away from being killed.

The poll was conducted after the resignation of director Kimberly Cheatle, who faced intense questioning at a congressional hearing that was broadcast live last week and in which she gave evasive answers. The new acting director Ronald Rowe said earlier this week that he was “ashamed” after the July 13 attack in Butler, Pennsylvania, saying he considered it indefensible that the roof used by the gunman was not secured.

During a news conference Friday, Rowe acknowledged the agency’s loss of trust from the American people. He said people generally only know about the agency’s failures — not its successes. He praised the agency’s staff who are quietly “working in the background” to protect political rallies, inauguration day and other events.

“We will earn back your trust,” he vowed.

The poll revealed that Americans were most likely to say that political division in the U.S. had “a great deal” of responsibility for the assassination attempt.

Half of U.S. adults say that, while about 4 in 10 say the Secret Service bears a high level of responsibility, and about 4 in 10 say the widespread availability of guns is greatly responsible.

Democrats were far more likely to blame the availability of guns while Republicans were more likely to blame the Secret Service.

Roger Berg, a 70-year-old farmer from Keota, Iowa, is planning to vote for Trump, the Republican nominee, in November. But he expressed discontent about Republicans blaming President Joe Biden for issues he thought Biden had no control over. Biden ended his reelection bid eight days after the shooting and has endorsed Vice President Kamala Harris, now the likely Democratic nominee.

“The people that are making everything about politics, I wish they would just quit,” Berg said. “They pin it all on Biden, and I don’t believe in that.”

Democrats, meanwhile, are substantially more likely than independents or Republicans to say the availability of guns bears a great deal of responsibility. Six in 10 Democrats say this, compared to about one-third of independents and 15% of Republicans.

Republican respondents were more likely than independents and Democrats to blame the Secret Service: About half of Republicans think the Secret Service has a great deal of responsibility, compared to around 4 in 10 Democrats and independents.

George Velasco, a 65-year-old Navy veteran from Tucson, Arizona, said he thought both the Secret Service and local law enforcement were to blame along with poor communication and a lack of proper planning. The Secret Service’s acting director said earlier this week that it was regrettable that local law enforcement had not alerted his agency before the shooting that an armed subject had been spotted on a roof, while also recognizing the Secret Service assumed that state and local police had presence.

“It was as if the Secret Service expected those guys to know what they had to do,” Velasco said. “It was a very small area, a small town. How did they expect them to know how to prepare for something huge like that rally?”

The poll found that half of Americans think local law enforcement in Pennsylvania had at least a moderate amount of responsibility for the assassination attempt, although only about 2 in 10 said it had “a great deal” of responsibility.

The Secret Service was first created as part of the Treasury Department to investigate the counterfeiting of U.S. currency during the Civil War. The agency began informally protecting presidents in 1894, according to the its records. Congress requested Secret Service protection of U.S. presidents after the assassination of William McKinley in 1901.

Protection was extended to the president’s immediate family, presidents-elect and vice presidents after a White House police officer was shot and killed while protecting President Harry S. Truman in 1950. It was later extended to former presidents in 1965. After the 1968 assassination of U.S. Sen. Robert F. Kennedy, who was running for the Democratic presidential nomination, Congress authorized protection of major presidential and vice presidential candidates.

About one-third of Americans are extremely or very confident that the Department of Homeland Security, which oversees the Secret Service, will conduct a full and fair investigation of the assassination attempt, while about one-third are somewhat confident and about 3 in 10 are not very confident or not at all confident.