WASHINGTON — Nobody can say that Sen. John Kerry hasn't learned from his failed 2004 presidential bid, which was seriously crippled by his inability to stake a crystal-clear position on the war in Iraq.

His latest call for a July 1, 2007, redeployment of all American troops from Iraq is a major gamble that puts him out on a politically risky limb as he tries to demonstrate the leadership that critics said he lacked as his party's nominee two years ago.

Two other Senate Democrats, Russ Feingold of Wisconsin, categorical from the start in his opposition to the war, and Barbara Boxer, another constant critic, joined Kerry in the timetable amendment to the Defense Authorization bill before the Senate. But the implications for Kerry are what stand out.

His sponsorship is an eye-opener because it is his most specific step to overcome the reputation for ambiguity on Iraq attached to him in the 2004 campaign. It follows his recent flat-out declaration to a conference of the party's leading liberal activists that he was wrong in voting for President Bush's war resolution in 2002.

Feingold, like Kerry, is considered a prospective candidate for the 2008 Democratic presidential nomination, but with neither the name recognition nor financial backing Kerry has for a second shot at the presidency. Feingold's support of the timetable is consistent with his vote against the same 2002 resolution that Kerry backed, and that haunted him through the 2004 campaign.

The teaming of Kerry and Feingold on this amendment is a pointed contrast from the time 38 years ago when two fierce critics of the Vietnam war vied for leadership of the Democratic antiwar movement, and both failed to be nominated.

In 1968, Sen. Eugene McCarthy of Minnesota, like Feingold today, stepped out of political obscurity to lead the war protest. McCarthy was challenged for the Democratic nomination by Sen. Robert Kennedy of New York, like Kerry today well-known and well-heeled. Kennedy bested McCarthy in the primaries but was assassinated the night of the Democratic primary in California, leaving the nomination to the establishment candidate, Vice President Hubert Humphrey of Minnesota.

In that election year, the Democratic Party entered the campaign on record in support of incumbent President Lyndon Johnson's conduct of the Vietnam war, but Johnson withdrew from contention for re-election as a result of the pressures of that war.

This time around, with the White House in Republican hands, the war position of the Democratic Party is being shaped by Sen. Carl Levin of Michigan, ranking Democrat on the Armed Services Committee. It merely calls for a troop drawdown to start by the end of this year, with no deadline for total redeployment. The House last week, including 42 Democrats, rejected such a timetable.

Kerry and Feingold, in so conspicuously calling for a firm date to wind down the American forces in Iraq, are gambling that public support of the war will continue to erode. The position is no switch for Feingold, who has been in the forefront of opposition to the Iraq war from well before Bush's invasion, and his antiwar credentials are unchallengeable.

Kerry, however, though he spoke out against the war when President Bush veered from the path of broader multilateral action through the United Nations, still labors under the earlier charges of inconsistency in his opposition.

At a minimum, Kerry's declaration of a date certain for an American troop withdrawal draws a sharp distinction with Sen. Hillary Clinton of New York, the Democratic frontrunner in the major presidential polls for 2008, who has called setting such a date unwise.

Kerry and Feingold, in addition to going beyond most of their own party on the issue, are already being tarred by Republican leaders as advocates of "cutting and running." Bush, at a party fundraiser Monday night, pledged "there will be no early withdrawal so long as we run the Congress and occupy the White House."

That first condition may be the key to his keeping that pledge. A Demo-cratic takeover in the November congressional elections could seriously disrupt his determination to "stay the course" in Iraq over his remaining two years in office.

Jules Witcover's memoir, "The Making of an Ink-Stained Wretch," has just been published by Johns Hopkins University Press.