The attempt by Russian hackers to infiltrate the email system of Sen. Claire McCaskill and her Senate staff was not a rare incident, a Senate colleague says.

Sen. Jeanne Shaheen’s office has been the target of at least one phishing attack for email and social media accounts, the New Hampshire Democrat said Sunday.

And it’s part of a larger pattern among congressional offices and political parties.

“There has been one situation that we have turned over to authorities to look into, and we’re hearing that this is widespread, with political parties across the country, as well as with members of the Senate,” Shaheen said on CBS’ “Face the Nation” on Sunday.

Phishing attacks span party lines, too.

“It affects both Republicans and Democrats. It’s about the security of our political process and our government functions and we need to work together to address it,” Shaheen said.

McCaskill said Thursday that Russian hackers did not successfully penetrate her Senate office’s computer systems, following a report that one of her policy aides was the target of a phishing attack.

McCaskill’s staff may have been better prepared than others on Capitol Hill. She has advocated for improved information security fluency and, as the top Democrat on the Senate Homeland Security and Governmental Affairs Committee, she has pushed for a more robust information security workforce.

“While this attack was not successful, it is outrageous that they think they can get away with this. I will not be intimidated,” the Missouri Democrat said in a statement Thursday. “I’ve said it before and I will say it again, [Russian President Vladimir] is a thug and a bully.”

Though the Senate still lags behind the House since it does not require staff to attend mandatory training sessions, the Senate Sergeant-at-Arms said in May it had hosted 52 cyber awareness seminars since the start of 2017.

Katherine Tully-McManus and Bridget Bowman contributed to this report.

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