EXCLUSIVE — Senate Majority Leader John Thune (R-SD) has no illusions about the challenges ahead as he tries to execute an ambitious conservative agenda, even with Republicans controlling the White House and both houses of Congress. He is already being put to the test on whether he can go big without overpromising. In a wide-ranging interview with the Washington Examiner after the certification of President-elect Donald Trump’s Electoral College win on Jan. 6, Thune touched on his legislative priorities, vision for budget reconciliation, and working relationships with the incoming president and House Speaker Mike Johnson (R-LA) that will prove crucial to his success. The sit-down interview in his new Senate office was Thune’s first with a print outlet since assuming his role at the start of the new Congress on Jan. 3. Thune called his...