Sen. John McCain (R-AZ) assailed Sen. Barak Obama (D-IL) as insincere, partisan, and a political opportunist in a letter responding to Obama’s decision not to join McCain’s bipartisan commission on reform. According to the Associated Press McCain wrote, “I concluded your professed concern for the institution and the public interest was genuine and admirable. Thank you for disabusing me of such notions.” Obama, in a letter responding to McCain, wrote that he had “no idea what … prompted” such vicious language. The leader of the Democratic reform effort, Obama, sounded disappointed, but did maintained a collegial tone, “The fact that you have now questioned my sincerity … is regrettable but does not in any way diminish my deep respect for you nor my willingness to find a bipartisan solution to this problem.”