In 2009, Obama basically had Grassley on speed dial, calling him frequently during negotiations over an overhaul of the nation’s healthcare system. Grassley at the time was one of three Republicans on the Group of Six, which also included Sen. Mike Enzi (Wyo.) and former Sen. Olympia Snowe (Maine).

“During that period of time, the president would call me on my cellphone and talk to me. I don’t know if it was a half a dozen times or a dozen times, but enough so you remember he called you,” Grassley said.

The relationship unraveled after a meeting at the White House in August 2009.

“We had a meeting down at the White House about Aug. 5, 2009 — the six of us — and he asked me this question: ‘Would you be willing to be one or two or three Republicans voting with the Democrats to get a bipartisan bill?’ and I said, ‘No,’ ” Grassley recalled.

“I never had a phone call from him since,” Grassley added.