Appearing for an interview on CBS's "Face the Nation," Graham also broke with White House senior adviser Jared Kushner, who last week downplayed Russia's interference in the 2016 election as "a couple of Facebook ads."
Graham noted that the Russians hacked Democratic emails and used social media to pit "one American against the other" in the 2016 election, saying that "an attack on one party" should be considered "an attack on all."
"Can you imagine what we would be saying if the Russians or the Iranians hacked into the presidential team of the Republican Party? This is a big deal," he said. "It’s not just a few Facebook ads. They were very successful in pitting one American against the other during the 2016 campaign by manipulating social media."