MILWAUKEE -- The Green Party chose a little-known California lawyer as its presidential nominee Saturday -- a serious blow to Ralph Nader and a potential boon to Senator John F. Kerry. Nader, the Green candidate in the last two presidential elections, sought the party's endorsement this year for his independent candidacy, a move that could have gained him ballot access in at least 22 states and the District of Columbia. Instead, after days of feverish debate, the Greens opted for David Cobb, 41, by a narrow margin.

That was good news for Kerry, the presumed Democratic presidential nominee whose campaign is worried about a repeat of the 2000 election. Nader was on the ballot in most states that year, thanks largely to the Green Party, and he was blamed by some -- and thanked by others -- for paving the way for Republican George W. Bush's narrow victory over Democrat Al Gore.

Cobb's nomination means that Nader now faces the arduous task of qualifying for the ballot on his own in the states where the Green Party has a ballot line. Many ballot analysts predict Nader will fall short in some of these states, which include the key battlegrounds of Wisconsin, Oregon, Minnesota, New Mexico, and Nevada.

By nominating Cobb, the Greens have a candidate "with zero name recognition," said Dean Spiliotes, a fellow at the New Hampshire Institute of Politics who specializes in presidential campaigns. "It may be a good exercise in building up the party on the local level, but it means the party will drop off the radar. It's a shock, but it is great news for Kerry."

Cobb's campaign strategy also should help Kerry. Cobb plans to avoid a hard sell in the states that Kerry and President Bush are most closely contesting, an approach that some have described as a "safe state" strategy.

His focus will be in states that are dominated by either the Republicans or Democrats, where he has said he will push progressives to vote Green as an "investment" in the party's future. That probably will include California, which Kerry is expected to carry easily and where the Green Party has a ballot line.

To qualify as an independent in California, Nader will have to gather more than 150,000 signatures of registered voters. The Green Party cochairman, Ben Manski, said the group hopes that by November, it will have qualified Cobb for the ballot in more than 30 states. But a clear rift within the party was created by Saturday's vote, and it may last, say party officials.

After Cobb was officially nominated, many Nader supporters stormed out of the ballroom. Some sobbed. Others cursed and threw their Green Party posters to the ground.

"This is a dark day," said Robert Nanninga, a delegate from Encinitas, Calif. "We've just nominated a white lawyer with a car salesman's smile. It might as well be a Republican. This is going to be remembered for years to come."

Earlier this year, Nader was endorsed by the Reform Party, which gives him ballot access in seven states, including Florida, Colorado, and
Michigan.