For months the supporters of the Equal Rights Amendment have fought on, refusing to admit defeat even when defeat seemed certain.
Finally, three states short and only six days to go before the ERA legally expires June 30, the National Organization for Women (NOW) has declared that its decade-long struggle is over. The constitutional amendment that would have added the words ''Equality of rights under the law shall not be denied or abridged . . . on account of sex'' will not be added to the Constitution, at least not yet.
A solemn but unbowed Eleanor Smeal, president of NOW, faced a battery of cameras on the ground floor of NOW headquarters here June 24 and pledged that the ERA ''countdown campaign has ended, but the fight for justice will continue.''
For the defeat, the NOW president blamed the Republicans for their open opposition, Democrats for failing to come through in the crunch, and the ''silent lobby'' of corporate America that profits from sex discrimination.
Victorious ERA opponents, on the other hand, insist that men and women would not support the controversial amendment once they had read between the lines. Opponents claim people came to realize the measure would have removed necessary legal protections for women.
Her organization will now turn its attention from the constitutional amendment, Mrs. Smeal said. Its new aim will be to build an ''independent third force'' in American politics, one that will be more responsive to human and women's rights. Stopping short of advocating a third political party, she pre dicted that the new force would include men and women ''who desperately want a new political order.''
Although supporters in Congress have already announced that they will reintroduce the ERA immediately after its ratification period expires June 30, Mrs. Smeal made it clear that NOW will turn to other priorities.
''We will not again seriously pursue the ERA until we've made a major dent in changing the composition of Congress as well as the state legislatures,'' she said and predicted that ''the next time it's voted on, it will be by bodies where almost half are women.''
''June 30th is liberation day,'' she said. ''We're not going to be cheerleading on the side anymore. We'll be direct participants.''
During the 10-year drive to win ratification in the 38 states required for a constitutional amendment, NOW members and their allies have learned much about politics, according to Mrs. Smeal.
''Unquestionably, the most significant and historic outcome of this campaign is that it will usher in a new era of direct political participation for women, '' she said, adding that those who lobbied for the ERA often found ''that they were better qualified to hold office than the men they were lobbying.''
Even as the time before the ratification deadline shortened, donations continued to pour into NOW at a rate of more than $1 million a month, Mrs. Smeal said. She estimated that NOW's political action committees will have $3 million to spend on next fall's elections.
The new strategy for NOW, which spearheaded the ERA drive when it passed Congress in 1972, will go beyond politics, however. Mrs. Smeal also announced a major new legal campaign to challenge sex discrimination and enforce the equal-rights amendments already in effect in 14 states.
Although she declined to list other industries, insurance companies, which offer differing rates for men and women, will be among those singled out. And she added that companies will face not only lawsuits but boycotts as well.
The announcement of the end of the hard-fought ERA campaign came from the woman who only five years ago took her first paid job to become president of NOW. Since then, the Pennsylvania housewife and mother of two teen-agers has led the charge for ratifying the amendment.
She has faced a formidable challenge. While at first so noncontroversial that it was supported by politicians ranging from Alabama's George Wallace to Massachusetts' Sen. Edward M. Kennedy, the ERA soon began to set off explosive debates as it came up in the legislatures. Phyllis Schlafly, the founder of Stop ERA, launched a national campaign.
While 30 states had ratified the ERA during its first year, the effort soon lost steam and began to drift backward. Only one state has ratified since 1975, and five have attempted to rescind their approval.
Few movements have hit Americans as deeply and emotionally as that for the ERA. It has gone to the core of how men and women view themselves. And even if it did not add equality of the sexes to constitutional guarantees, it has not left the nation untouched.
As supporters mourn their loss, many are now beginning to examine the last 10 years and point to the progress. They lost the battle, but they say they are winning the war for the hearts and minds of America.
From Little League teams now open to girls, to the language we use, to the fact that more than half of all college students are female, the evidence shows that changes have already come, partly because of the push for the ERA.
On the legal front, femininsts point to federal equal-pay laws, the 14 states that have added equal-rights amendments to their state constitutions, and laws that require public schools to offer equal opportunities to both sexes.
Such changes have made a difference for women such as Donna Brazile, who was a track and basketball star in her Louisiana hometown. At first she was advised that her athletic skills would be of little use to her as a girl.
But by the time she finished high school in 1977, she had seen a transformation. Stories about her team had moved from the back pages to the front of the local paper, and she won a full athletic scholarship to Louisiana State University, a feat virtually unknown for women a decade before but now increasingly common.
Despite optimism, some in the women's movement worry out loud about possible regression. ''I think we will see some backsliding,'' says Kate Rand Lloyd, editor of Working Woman magazine, while visiting Washington. ''There is fear and terror about what is happening to women. It scares people.''
The magazine editor cites a study indicating that women managers begin to feel resistance from male peers once the female percentage reaches higher than token numbers.
She also cites the political right who ''truly believe that women should go back and sit at home because that's her place.'' And like many other ERA supporters, Ms. Lloyd points to the Reagan administration, which she says has hurt women by budget cuts in traditionally female areas (such as the arts and social services) and by appointing few women to prominent posts.
In the face of such warnings of backsliding, many feminists continue to see hope, especially in the growing political power of women. They have entered politics in greater numbers than ever before, tripling their ranks in legislatures since 1969.
But perhaps even more important, women have finally fulfilled a prediction made 60 years ago. In the 1980s women voted in far fewer numbers for President Reagan than did men, and in recent polls women have shifted noticeably to the Democratic Party.
''The women's voting bloc was what we hoped for in the '20s,'' says Elizabeth H. Pleck, a historian with the Center for Research on Women at Wellesley College in Wellesley, Mass. Then President Warren Harding and others made concessions to women in expectation of a woman's vote. When women turned out to vote just as men did, they stopped making concessions, she said.
If the current trend continues, it could provide the foundation for a ''new political force.'' The exact shape of that force is not yet clear, however. Some Republicans see the ''gender gap'' as basically a ''peace-war'' issue and not as demand for women's rights.
Still, the GOP Senatorial Campaign Committee is urging candidates to be aware of the so-called compassion issues and to consider hiring women for top campaign spots.
One candidate for reelection who appears to be listening to the ''woman's vote'' is Sen. Orrin G. Hatch (R) of Utah, a conservative who had proposed an amendment to weaken federal laws on equal opportunity for the sexes at schools. After intense lobbying, the senator announced that he would no longer push for the amendment.
Meanwhile, a staunchly anti-ERA White House has been keeping a low profile on the woman issue as the ERA nears its deadline. ''Emotions are so high,'' explains Wendy Borcherdt of the White House office of public liaison. ''We feel , let the ERA take its course. We have just not been for it. We have not lobbied against it.''