"I'll leave that up to them," Graham added, when asked if the White House should withdraw the nomination. "But I think that one will be a problem."

Canterbury's nomination had been on the Senate Judiciary Committee's agenda prior to a two-week recess earlier this month.

But since the Senate's return, he's been noticeably absent from the list of nominations that will be taken up during the committee's weekly business meetings even as other controversial nominees — including circuit court picks "Sul" Ozerden and Steven Menashi — are scheduled to get a vote.

But Canterbury is the subject of steep GOP opposition within the committee.

Canterbury, who was previously president of the National Fraternal Order of Police, rankled senators during his hearing before the Senate Judiciary Committee earlier this year by dodging their questions or giving vague answers when it came to his views on firearms.