Washington (CNN) Sen. Lindsey Graham said Friday that revelations in a newly released Justice Department report about the 2016 election have "crippled" the credibility of the department and the FBI.

He added that disclosures such as text messages between FBI agent Peter Strzok and former FBI lawyer Lisa Page that suggest they would block Donald Trump from winning the 2016 election have made Graham reconsider whether there was political bias in the FBI at the time of several sensitive investigations.

"Here's the point you got to get," the South Carolina Republican said on an interview with CNN's Kate Bolduan on "At This Hour." "Just back up. The institutions are crippled. If you don't believe that the average American is going to think that the FBI is far more political than they ever believed, that's crazy," Graham said.

The Justice Department's inspector general released a sweeping report Thursday detailing a series of failures by the top federal officials in charge of the investigation ahead of the election, concluding that the FBI's actions ultimately "cast a cloud" over the bureau and senior leaders did lasting damage to the FBI's reputation.

"I think most people will take from this, particularly the Republicans ... that the institutions investigating President Trump took a real blow here," Graham said.

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