Few of John Courson’s friends and constituents expected this. The veteran state senator and US Marine veteran who represents the Irmo area this week resigned his senate seat. He also pled guilty to official misconduct involving money laundering through his political advisor Richard Quinn, Sr., using campaign money for personal expenses. He agreed to cooperate with Special Prosecutor David Pascoe in his Statehouse corruption investigation. His agreement was announced as his trial on corruption charges was about to start Monday. Courson, 77, said after leaving the courtroom that he has health problems including high blood pressure. Sen. Courson still faces up to 10 years in prison. Judge Carmen Mullen deferred sentencing. Former S.C. Democratic Party Chairman and Columbia attorney Dick Harpootlian said he is “seriously considering” running for Courson’s seat. The Chronicle has asked two Senate leaders who represent Lexington County – Senate Majority Leader Shane Massey and Senate Minority Leader Nikki Setzler for comment.