Republican Sen. John McCain accused his Democratic colleague Barack Obama of "partisan posturing" on the issue — a charge Obama called puzzling and regrettable.
The exchange, made in letters between the pair, was the latest sign of trouble as the two parties try to come up with legislation governing relations with lobbyists.
Based on past Obama statements, "I concluded your professed concern for the institution and the public interest was genuine and admirable," McCain wrote in a letter to Obama on Monday. "Thank you for disabusing me of such notions."
"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," Obama wrote.
"I've never seen anything like it," said
"It's very clear that lobbying reform is a very personal issue for John McCain, it's very important to John McCain. He believes Sen. Obama gave him a private assurance to work with him on bipartisan reform," Borger said. "He thinks Sen. Obama backed out for partisan reasons because like most Democrats, Sen. McCain thinks, Sen. Obama would rather have the issue than solve the problem heading into the 2006 election."
McCain was responding to an earlier Obama letter in which the first-term Democrat last week thanked McCain for including him in bipartisan talks on lobbying reform but expressed some differences in approach to the issue spurred by recent lobbying scandals.