Sen. John McCainJohn Sidney McCainBiden falters in pledge to strengthen US alliances 20 years after 9/11, US foreign policy still struggles for balance What the chaos in Afghanistan can remind us about the importance of protecting democracy at home MORE on Sunday doubled down on his call for a select committee to investigate Russia's role in the presidential election while dismissing comments from Donald TrumpDonald TrumpTrump takes shot at new GOP candidate in Ohio over Cleveland nickname GOP political operatives indicted over illegal campaign contribution from Russian national in 2016 On The Money — Dems dare GOP to vote for shutdown, default MORE about the matter.
"We need to get to the bottom of this. We need to find out what was done," the Arizona Republican said on CNN's "State of the Union."
"There's no doubt they were interfering, and no doubt there was a cyber attack."
Both the FBI and CIA have concluded that Russia interfered with the elections to help Trump win.
But Trump has dismissed the allegations, saying there is no proof that Russia hacked into the email accounts of Democratic National Committee and Clinton campaign staffers.
McCain said while he hasn't heard Trump criticize Russian President Vladimir Putin, he suspects that "reality is going to intercede at one point or another."
McCain instead focused his criticisms on President Obama, saying the U.S. has been "totally paralyzed" in responding to Russia's attacks.
"The fact is that they're hacking every single day in other areas of our military and other aspects of American life, and we have no strategy, nor do we have any policy toward that," he said.
"This is serious business," McCain said.
"If they're able to do harm to the electoral process, then they can destroy democracy."