WASHINGTON, D.C: While House and Senate Republicans struggle to get their two budgets to button in the middle, President Clinton is in the political catbird seat, safely above the fray and loving it. Tuesday, Clinton was offering political cover to legislators who support hiking Medicare premiums for wealthy seniors. "I would be happy to defend the vote of any member of Congress, Democrat or Republican, who votes for this," Clinton said. He also proposed that the Treasury Department collect the premium increases rather than the IRS, so that seniors don't get confused and think they're faced with a tax hike. "It's very important now to complete the job and get a balanced budget agreement," Clinton told reporters. "We've now come back and offered them another way to do this, which I'm very hopeful will break the impasse and allow us to go forward." Clinton has been stumping for a deal by Thursday, so that he can hammer out a deal with congressional leaders before Congress goes on summer vacation August 1. Meanwhile, the publicity is risk-free. Clinton knows he's not the one who has to hurry: if Congress leaves without a budget deal, the hapless Republicans will be the ones to suffer, and their new Republican leader in the White House will have done all a man can do.