According to the Hill, the Senate’s most vulnerable Republican in next year’s election is open to designating a special prosecutor to investigate links between the Trump campaign and Russia.

Sen. Dean Heller (R-NV) told reporters this week that he would support the appointment if investigations by the House and Senate experience difficulties in the wake of FBI director James Comey’s termination.

“I’m uncomfortable with the timing of all this, and that’s why I think an independent prosecutor should be on the table if in fact the select committee in the Senate and the House cannot get to answers,” said Heller.

The senator is joined by colleagues Richard Burr (R-NC) and Mark Wagner (D-VA) in his concern for possible obstacles to the investigations. According tothe New York Times, the chairman and vice chairman of the Senate Intelligence Committee are heading up the most involved investigation on Russia, just last month asking Trump campaign associates for records of their contacts and other dealings with Russians.

Burr said he was “troubled by the timing and reasoning” of the director’s firing, adding that it “further confuses an already difficult investigation by our committee.”

Potentially complicating matters, the president told NBC’s Lester Holt on Thursday he had already determined to fire Comey, regardless of whether or not he received a recommendation from the Justice Department. He also indicated the Russia investigation factored into his decision, saying, “I said to myself, you know, this Russia thing with Trump and Russia is a made up story, it’s an excuse by the Democrats for having lost an election they should have won.”

To date, calls for a special prosecutor have gone unanswered, with Senate Majority Leader Mitch McConnell indicating he sees no reason to move in that direction.