But now, with Election Day just over the next hill, many of the groups that long have admired Nader's efficacy - and seemed to have a Springtime crush on the Green candidate - are dedicating themselves to stopping his insurgent bid for the White House.
Attacks against the Green Party presidential candidate are mounting from those once closely aligned with his progressive views but now angered by his refusal to step aside in closely contested states where a vote for Nader could mean a victory for Bush.
"I have seen acts of betrayal I just can't believe," Nader said Wednesday in Madison, Wis.
He admonished the Democratic "dirty tricks" used to undermine his candidacy, saying they were led by "desperate surrogates of the Gore campaign."
Among those supporters-turned-critics: The Sierra Club, The League of Conservation Voters, United Steelworkers of America, The National Abortion and Reproductive Rights Action League, AFSCME, the National Organization for Women, and the Human Rights Campaign. The groups join at least 20 Democratic senators and congressmen, and other progressives, who have been stumping for Gore.
Nader's insistence that there's no major difference between the major-party candidates, Bush and Gore, has been a touchstone for the anti-Nader movement in recent weeks.
"That's absurd. Ludicrous," said Ken Cook, president of the Environmental Working Group, of Nader's oft-repeated contention that Bush and Gore are peas in a pod.
Where Cook has taken President Clinton and Vice President Gore to task on numerous issues, a Bush administration would bring "excruciating consequences" for the public interest community, Cook said.
"Virtually everything the environmental community has achieved over the past thirty years could be at stake," Cook wrote in a letter to Nader.
Nader was urged to drop out of the race in another letter sent Wednesday by George Becker, president of the United Steelworkers of America.
While referring to themselves as "steadfast allies," Becker warned Nader against continuing to claim few differences between Bush and Gore.
Any advances made in workers rights, achieving a living wage or eliminating corporate influence in government would be reversed if Bush wins the election, Becker said.
"It would be tragically ironic if your dedication to principle should ultimately result in the further domination of our political process by the very forces of corporate greed that we have both worked so hard to restrain," he said.
Women's groups also are unhappy with Nader, a longtime supporter of abortion rights. They are furious over Nader's statements on the nation's landmark Supreme Court ruling, which protects a woman's right to choose.
"Even if Roe v Wade is reversed, that doesn't end it," Nader said over the weekend. "It just reverts it back to the states."
Rep. Nita Lowey, D-N.Y., called the comment "reckless and irresponsible," arguing that legislators and governors in 16 states are "chomping at the bit to outlaw abortion, to enact more restrictions, or make access even less private and more dangerous."
And Planned Parenthood director Gloria Feldt said Nader "just doesn't seem to care" about women's rights.
But Nader defended his record on abortion rights as better than many Democrats, who helped confirm the nominations of Supreme Court Justices Antonin Scalia and Clarence Thomas, considered the two staunchest conservatives on the bench.
"It's the Democrats that sent Scalia and Thomas to the Supreme Court, and in a total reversal of the historical record, NARAL tried to indicate that I want more Scalias and Thomases on the Supreme Court," Nader said.
Overall, Nader remains dismissive - and sometimes amused - by the appeals for him to drop out. Even pleas by former colleagues, including a dozen so-called Nader's Raiders for Gore, fail to sway him.
If Gore can't beat the "bumbling Texas governor with that terrible record," then, said Nader, "he ought to go back to Tennessee to his tobacco farm."
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