In fall 1967 Eugene McCarthy decided to force what he referred to as “a referendum on Vietnam” by launching an antiwar challenge to President Johnson. It was a courageous act. At the time polls suggested that while Americans were frustrated about the course of the war, their preferred solution was not the exit strategy McCarthy counseled but escalation. Democrats who oppose the current military engagement in Iraq face no such challenge. This fall’s polls show a substantial majority of Americans believe the country should start bringing the troops home. And with the call by one of Congress’s most decorated veterans, John Murtha, for establishing a withdrawal timeline, all but a handful of Congressional Democrats–and even some responsible Republicans–are beginning to talk about exit strategies. That does not mean, however, that everyone agrees about what must be done, or that an end to the war is in sight. But it does mean the Iraq debate has evolved from a contest over how to manage the US occupation into the question of whether the occupation should continue. That question will be a central–perhaps the central–issue of the 2006 Congressional elections.

In our November 28 cover editorial, “Democrats and the War,” we took the stand that “The Nation will not support any candidate for national office who does not make a speedy end to the war in Iraq a major issue of his or her campaign.” We urged voters to join us. In recent weeks, as more Democrats have spoken out against the war and for a timely exit, we have come to believe even more firmly that antiwar candidates, with the requisite credentials, can prevail next fall. The first step in that process is, of course, to encourage support for such candidates, as we are doing this week and as we will continue to do throughout 2006.

Among leading Democratic Representatives and strategists, there is a palpable unease about laying out a withdrawal timeline. The DC insiders fear that doing so might provoke a voter backlash, despite the evidence of the polls. It is encouraging that recent weeks have seen significant if incomplete movement in the House Democratic caucus toward embrace of an exit strategy, especially since minority leader Nancy Pelosi endorsed Murtha’s plan.

But the same cannot be said for the Senate caucus, which continues to send dramatically mixed messages. A handful of members, like Russ Feingold, clearly support a timeline, but others, like Joe Lieberman, still back Bush’s “stay the course” talk. And top Democrats, like minority leader Harry Reid and Hillary Clinton–who has attracted an antiwar primary challenge from former National Writers Union president Jonathan Tasini–continue to try to have it both ways, expressing ever-increasing impatience with Bush’s approach but rejecting a firm exit strategy. Clearly, the Senate could use more Feingolds. But that shift will not occur simply by electing Democrats in the half-dozen contests where seats are open or where Republican incumbents are weak. The key is to elect the right Democrats, or to force the wrong Democrats to get right about Iraq. That prospect now seems increasingly viable in the states where the most competitive Senate races are playing out; in most of them there is at least one serious antiwar contender. The outcome of these challenges is as uncertain as McCarthy’s was in December 1967. But the value of every serious antiwar candidacy, even those that merely put pressure on eventual nominees to clarify their stances, is beyond debate. While contests in the House are often hard to “nationalize,” Senate races tend to focus on national and international issues, and as the 2006 competition gears up, they are attracting more antiwar contenders than at any time since the late 1960s and early ’70s, when opponents of the Vietnam War made virtually every Senate contest a referendum on the war.

Take the case of Rhode Island. Matt Brown started out as the decided underdog in the contest for the Democratic nomination to take on vulnerable Republican Senator Lincoln Chafee. But Brown, the Rhode Island secretary of state, is pushing for a timetable to bring the troops home by the end of 2006, and like a number of other antiwar candidates he is forcing not just his primary opponents but his party–which has begun to see the Rhode Island contest as pivotal in the fight for control of the Senate–to get serious about getting out of Iraq. In the primary Brown faces former state attorney general Sheldon Whitehouse, a much more cautious contender. Whitehouse is backed by the state’s two Democratic Congressmen and has a clear fundraising advantage, but Brown’s got the issue. Since August, when Feingold became the first senator to urge a specific timetable for withdrawal, Brown has been calling on the Administration to bring the troops home in 2006–and the 36-year-old former community organizer hasn’t backed off since. Whitehouse is feeling the heat and now says he’s for a “flexible” withdrawal timeline. But Brown says, correctly, that anything less than a precise timeline plays into the hands of an Administration that seeks an open-ended commitment to military occupation.

Brown is not alone. In Pennsylvania college professor Chuck Pennacchio proposed an exit strategy in June, forcing primary front-runner Bob Casey Jr. to at least begin talking about the failure of the Administration to define its goals in Iraq. In Montana John Tester, a leading contender for the Democratic nod, announced in November, “The time has come to support our troops by laying out a plan to bring them home.” In Minnesota, where Democratic Senator Mark Dayton, a war critic, is retiring, child-safety advocate Patty Wetterling, who has emerged as one of the strongest contenders for the Democratic-Farmer-Labor Party nomination, announced her candidacy with a promise to make an exit strategy her top issue in 2006. “Next Thanksgiving I want us out of Iraq,” she says. Like Brown, Wetterling has launched a petition to pressure the Administration for an exit strategy.

In Maryland the most prominent contenders in a multicandidate field to replace retiring Democratic Senator Paul Sarbanes are Representative Ben Cardin and former NAACP chair Kweisi Mfume. Both are war critics, but Mfume, whose campaign struggled initially to match Cardin’s fundraising and organizational strength, has sought to distinguish himself as the antiwar candidate by criticizing Cardin for failing to support Representative Lynn Woolsey’s May 2005 amendment calling for a withdrawal timeline. Mfume is now in a dead heat with Cardin.

In Ohio a leading backer of the Woolsey amendment, Representative Sherrod Brown, has entered the Senate primary race against Paul Hackett, the Iraq War veteran who was bluntly critical of Bush’s handling of the war during a losing race this past summer for an open House seat. In his House race Hackett surprised many fans of his anti-Bush remarks by opposing a timeline for withdrawal, and he has since disturbed war critics by dismissing the Congressional push for a timeline as “absolutely ludicrous.” There is no such ambiguity with Brown. He was an outspoken foe of the 2002 resolution authorizing Bush to use force in Iraq, and since the start of the war he has written House letters demanding answers from the Administration about the misuse of prewar intelligence, co-sponsored withdrawal resolutions and regularly read letters from antiwar constituents–particularly members of military families–into the Congressional Record.

Even some Democratic incumbents are feeling the heat. Since Lieberman has emerged as the Administration’s loudest Democratic defender, he has taken criticism from grassroots Democrats and groups like Democracy for America. Lieberman is unlikely to face a substantial antiwar challenge in the Connecticut primary. But he could still face serious opposition: Former Senator Lowell Weicker, a liberal Republican turned Independent, is talking about mounting a “Bring the Troops Home” challenge come fall (see John Nichols, “Run, Lowell, Run,” in his “Online Beat” blog on this site).

There will be plenty of twists and turns between now and November. But if Sherrod Brown wins in Ohio, where Republican Senator Mike DeWine is vulnerable, and Independent Representative Bernie Sanders wins Vermont’s open seat, as now seems likely, two of the House’s most articulate and savvy antiwar voices will be heard in the Senate. And if they are joined by others, like Minnesota’s Wetterling, Montana’s Tester or Rhode Island’s Matt Brown, the Democratic leadership will get the message loud and clear: It’s time to get out of Iraq.