In an election with the most profound of issues on the table - terrorist threats at home, Americans at war abroad, and an economy in flux - the presidential campaign has become consumed by a tangled dispute over events that took place more than 30 years.
And the issue, Democratic nominee John Kerry's Vietnam War record, is not likely to go away anytime soon. Tuesday, the principal group disputing Senator Kerry's record will launch a new TV ad that takes on Kerry's antiwar activism in the early 1970s and its devastating impact on some veterans.
As with the earlier ad produced for the group Swift Boat Veterans for Truth, the new spot will air in only three states with a limited budget. But attention to it, via free media, will be enormous. Kerry and his supporters, including the Democratic National Committee and outside groups such as Moveon.org, will also add to the media hurricane. Expect a revival of the debate over President Bush's lack of service in Vietnam and lingering questions over his record in the Texas Air National Guard, analysts say.
"The net effect of this has been to make an already very partisan race even more partisan," says John Kenneth White, a political scientist at Catholic University.
The controversy has presented Kerry with an acid test of his political skill. He has sought, until late last week, to take the high road and not respond personally to the allegations by the veterans group. When the group's first ad debuted on Aug. 5, Kerry relied on defenders to shoot down its allegations, that Kerry did not behave heroically or deserve all of his medals. By the end of last week, with a CBS News poll showing a nine-point drop in support for Kerry among veterans since the Democratic convention, he knew he had to respond himself.
In a tight race, every voter bloc matters. And as the lessons of past campaigns have shown, allowing charges to fester can be politically fatal. Even if voters don't follow every twist and turn of a complicated story, doubts about claims of heroism - which ultimately could translate into doubts about Kerry's honesty and character - could at the very least cause potential Kerry voters to stay home on Election Day.
"The danger for Kerry with the undecideds is, if this issue goes back and forth, it leaves people confused and the undecideds don't vote," says Del Ali, an independent pollster who is about to survey veterans on the swift-boat flap.
Efforts in the media to fact-check the allegations of Kerry's opponents reveal an incomplete record of the incidents in question - including one in which Kerry saved a green beret's life - but one that still weighs in favor of the veracity of Kerry's claims.
An investigation by The Washington Post published Sunday found that both sides have yet to make public all records, including Kerry's diaries, related to the incident in March 1969 when Kerry rescued Jim Rassmann, the former Green Beret who now appears in ads for the senator. But the report also concluded that Kerry's opponents have not proved he lied.
Another Kerry defender stepped forward over the weekend after 35 years of silence over a different incident, one that took place on Feb. 28, 1969. William Rood, the only other surviving swift boat commander to witness the incident, wrote a piece backing Kerry's version of events in the Chicago Tribune, where he works as an editor. The incident, for which Kerry won a Silver Star, involved Kerry chasing down a Vietcong gunner and killing him.
Kerry's opponents claimed he had chased down a Vietcong teenager "in a loincloth" who may or not have been armed. Mr. Rood described the gunner as "a grown man, dressed in the kind of garb the VC usually wore." Kerry's Silver Star citation indicated the man had a B-40 rocket launcher with a round in the chamber.
Rood also took offense at the Swift Boat vets group's actions for having "splashed doubt on all of us."
Analysts say that the veterans' efforts on behalf of Bush - which the Kerry campaign claims are in fact being orchestrated by the Bush campaign itself, in violation of campaign finance laws - run the risk of producing a backlash against the president. In an election where voters are eager for a sense of vision from each of the candidates, the swift-boat flap has drowned out discussion of current policy issues. The Bush campaign says it will unveil its agenda for a second term at the Republican National Convention, which begins in a week.
But Bush administration officials also say that Kerry's reaction to his opponents is a substantive matter - referring to the senator "losing his cool" in a way reminiscent of Bush's attacks against John McCain when the Arizona senator ran against Bush for the Republican nomination in 2000. The implication is that Kerry lacks the temperament to be president.
Still, there's a big difference between Bush vs. McCain in 2000 and Bush vs. Kerry in 2004: In 2000, when McCain reached his Waterloo in the South Carolina primary and was savaged by an outside group's ad, he was also out of money at that point and found it hard to fight back effectively. In August 2004, Kerry is not out of money. Now he faces the challenge of putting allegations over claims of lying about his war record to rest - and then regaining momentum on issues.
"This guy is a fighter," says Democratic strategist Jenny Backus.
And as Democrats know well, so is Bush.
• Christina McCarroll contributed to this report.