Reacting to a report two days ago that U.S. District Judge Leigh Martin May rejected Graham's argument that his calls to Georgia secretary of state Brad Raffensperger about the 2020 presidential election results were protected under the U.S. Constitution's "speech or debate" clause, means he now has to appear, Pate said the South Carolina Republican, at this point, must comply.

Speaking with CNN host Sara Sidner, Pate was asked what is next for one of Donald Trump's most ardent supporters.

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"I think the grand jury wants to know what Senator Graham said to the secretary of state and they want to hear, and they already have heard from our secretary of state that he felt not just Trump's call was an attempt to persuade him to do something potentially illegal but the secretary of state thought the calls from Senator Graham also were encouraging him, or at least attempting to encourage him, to do something illegal."