It's time to cleanse D.C., and luckily, these two are steady, not slippery

ST. PAUL, Minn. — Change is coming, change you can count on.

That is the simple, central message from the two presidential nominating conventions held in Denver and St. Paul during the past two weeks.

Whether it is Barack Obama or John McCain going to the White House next January, the new president will understand that his mandate from the voters is to cleanse Washington of its excessive partisanship and attempt to break the gridlock that has prevailed on almost all the big issues.

The good news is that Obama and McCain, for different reasons, have about as good prospects of achieving that change as any two politicians you could find.

The acceptance speeches they delivered will not find places in many collections of great campaign oratory. But rhetoric aside, the clear intent of both candidates was to signal that they understand the frustration of voters of all parties with the poisonous status quo of recent years in Washington.

There is reason to think that Obama and McCain would actually fulfill the voters' hopes for a chief executive who would be a catalyst for change. Obama, who is 47, is the first post-boomer politician to come this close to the presidency. The baby boomers — Clinton, Bush, Gore, Gingrich and the rest — have been cursed by their heritage. They came of age during the turmoil of civil rights, women's rights and Vietnam, and their generation has never stopped refighting the battles of those tumultuous years.

Obama is too young to have experienced those fights, so his mind is open to ideas and information from a far greater variety of sources. He has fewer scores to settle, so he can serve more freely as an arbitrator.

McCain, who is 72, is almost but not quite a throwback to the "greatest generation," the one that survived the Depression, won World War II and built the international architecture of the postwar world. With the McCain family military tradition and the high patriotism forged by his own experience as a prisoner of war, McCain — like the heroes of FDR's and Truman's time — disdains partisanship and searches for the national interest, wherever he can find it.

Their skills and agendas are different, but both McCain and Obama bring strengths to what will obviously be a struggle against the forces of parochialism and partisanship resisting change in Washington.

Obama has an exceptional mind when it comes to analyzing and then formulating policy. His methods are reflective and sometimes iconoclastic, but the results are impressive. He has outlined approaches to domestic issues that might actually enlist support across a broad political spectrum. Still, his skills as a negotiator are largely untested, and he has yet to demonstrate, as McCain has, the backbone to challenge the prevailing interest groups in his own party.

McCain, for his part, is far more dependent on others for the detailed working out of policy. His real strength lies in personal relationships; he is at his best when negotiating a deal — and in knowing what it will take to make the deal stick. On the international side, he has a better feel for the personalities involved than Obama at this point — and probably more comfort in dealing with them.

Neither of these men has much experience in managing a large bureaucracy, so there is no way to judge how well they will cope with that aspect of the Washington challenge. Both are products of the Senate, but congressional recalcitrance will test them as much as any new president. One would have to give McCain the edge on both his willingness and ability to confront the demands of a Democratic Congress.

Over the next two months, the campaign will teach voters more about how each of these men would approach the governing challenges. The contest between them looks closely competitive, with battlegrounds extending from Virginia to Nevada.

Each of them has acquired a running mate who complements their own strengths, and each was bolstered by their conventions. It is a fair fight, and one the country can anticipate with good hope.

David S. Broder's column appears Sunday on editorial pages of The Times. His e-mail address is davidbroder@washpost.com