THERE'S a kind of gentle joke that travels through the halls of the National Organization for Women (NOW). It's called a ''smealism,'' after the group's former president, Eleanor Smeal.
As one admirer says, ''smealisms'' are what spatter from the soapbox when Ms. Smeal's ''mind works faster than her tongue.''
Ms. Smeal once declared, for instance, in her hometown Pennsylvania accent, ''I wasn't born yesterday for nothing!'' Another time she encouraged audience with, ''Let's roll up our arms and get to work!''
The soapbox feeling comes early and often in an knterview with Ms. Smeal, women's rights advocate, spokesperson for the homemaker, leader of the pro-Equal Rights Amendment faction.
''Ellie is a great motivator of people, largely through example,'' says a close associate at NOW, where the former president saw membership grow from 50, 000 to 250,000 under her leadership and take an increasingly political turn.
If women in the United States seem to be delving more into politics, with larger numbers votino and running for political office, much of the credit goes to NOW. Both admirers and detractors of the women's movement concur that the ongoing fight for the ERA, championed by NOW, has helped focus national attention on inequities in the ways women are treated under the law.
The fight has also, says a source at NOW, created the so-called gender gap - the difference in a politician's standing among male and female voters. ''Ellie was the catalyst for the gender gap,'' says an admirer. Ms. Smeal herself doesn't quite agree with that assessment. ''We felt like Christopher Columbus,'' she said in the interview. ''America was here; he discovered it. The gender gap was there; we discovered it.''
In her newly published book, ''Why and How Women Will Elect the Next President'' (New York: Harper & Row), she claims that the differences between men's and women's votes were never tracked before because, unlike many minority groups, women don't live in a particular voting district or area.
Ms. Smeal and others had suspected that women vote differently from men, and they felt a need to prove their hunch, she says, during the ERA fight. Armed with polls showing the voting populace favoring the ERA (''2 to 1,'''she says), she and others would visit members of the state houses to persuade them to vote in its favor. ''First they'd say, 'My district doesn't feel that way,' and we'd show them the polls. Then they'd say, 'My constituents don't feel that way,' and we'd show them the polls. Then they'd say, 'Maybe women are in favor of the ERA, but they just vote the way their husbands do.' Always the denial,'' she says.
NOW began tracking the votes of men and women separately, first by using exit polls after the 1980 election. These indicated an eight-point gender gap between men and women voting for Reagan. Then they followed Reagan's popularity polls, ''because he's anti-ERA, and because they're taken monthly.''
What they found, she claims, is a gender gap that has moved from general anti-Reagan feelings toward support for candidates who favor government spending on social issues, such as ''education and the environment, and decreasing military spending,'' she writes.
The women's vote will make all the difference in the presidential race, she insists - especially if one of the parties chooses a female vice-presidential candidate. A study she recently completed for the Democrats indicates that thd choice of a female running mate would give any candidate a 10-point boost in the polls. ''Can you imagine what would happen if a poll said that, say, a white male from Illinois would cause a 10-point boost? They'd be busting down the doors in Illinois, creating a candidate if they couldn't find one,'' she asserts.
Instead, the talk about a woman vice-president - including Eleanor Smeal as a possible choice - is still just talk, a fact that rankles some feminists. Ellen Goodman said in a recent column that women should be emulating the style of candidate Jesse Jackson, who isn't waiting for the Democratic Party to nominate a black man, but is actively seeking the nomination himself.
Ms. Smeal agrees, but adds rather sadly, ''We just don't have the confidence factor in the movement yet. The blacks have been working for civil rights since the '50s, and we didn't start until the late '60s, so we're further behind, I guess.''
One sign of this is that ''some people still think you're nuts if you go out and advocate justice for half the human race,'' she says. The kind of justice she has in mind is the kind that actively enforces equal rights laws and keeps employers from paying and advancing womej at dz - rates than men (''they enforce the laws against robbers, and this is a kind of robbery, isn't it?'').
Her sense of justice also includes laws protecting the rights of those wanting abortions, an issue she thinks will loom large in the coming election. She believes that once the public understands that Mr. Reagan's anti-abortion position is against all abortion they will rally to the other side.
Ms. Smeal now makes what appears to be a comfortable living. Among other things she acts as a consultant to female candidates. Her speaking engagements, work as Capitol Hill ERA liaison for NOW, and the publishing of her women's rights newsletter (The Eleanor Smeal Report) help pay for a spare but ample office at the posh Watergate, shared by a small staff - including husband Charlie.
This is a new career style for the team that started out as a small-town Pennsylvania couple some 21 years ago, a blend of two close-knit families. ''We've spent every vacation either visiting relatives or taking care of them,'' she says.
Both joined NOW in the '70s when they discovered that her work as a homemaker was not considered economically reimbursable - ''worthy,'' as she puts it - by the Social Security Administration after an illness left her temporarily unable to perform those duties.
Ms. Smeal, who speaks of the ERA battle as a ''great historical fight,'' worked to expand NOW into suburban areas. ''I opened the first suburban chapter, '' she says.
''Ellie is known for running through large numbers of people in a day - no one can keep up with her,'' says current NOW president Judy Goldsmith. By ''super organizational ability'' and by working 20-hour days, Ms. Smeal reached the top of the organization and made it what admirers call a ''strong mainstream force.''
With more mainstream women - like Betty Ford, co-chairman of the ERA Countdown Campaign - joining its cause, NOW no longer carries the radical label it once flaunted. Ms. Smeal herself may be a large reason for that middle-road respectability. As a mother of two (her eldest is in college) and former full-time homemaker, Ms. Smeal gave the women's movement the appearance of fighting for the average American woman. Says a homemaker and longtime admirer, ''Other feminists told us to get out of the house and get equality on the job. Ellie Smeal worked for homemakers' rights.''
NOW, the vehicle for feminism she steered'into vhe '80s, ''is like family,'' says Ms. Smeal. ''There's a lot of rough-and-tumble.'' Perhaps that explains the caustic rumors within that she built up an empire at NOW - one, they say, she still runs through her hand-picked successor.
Ask the successor about that theory, and you get loud groans. ''What Ellie did, she always did to further the goals of the organization, not for any kind of self-aggrandizement,'' Ms. Goldsmith declares.
Ms. Smeal admits that she has a reputation as ''a strong leader - I'm a mover ,'' but she says that the big decisions - which states to lobby for the ERA, for instance - were made democratically by ''literally hundreds of chapter presidents and leaders.'' And while she admits that there are ''factions'' within NOW, she thinks such ''rough-and-tumble'' is ''healthy - it's a rough-and-tumble world we live in, and you need practice dealing with it.''
She also thinks that the women's movement as a whole - despite some contentiousness within - is united on several fronts right now and ''burgeoning. It's just starting to flower,'' she says.