Hillary Rodham Clinton has abdicated the role of first lady to run for a U.S. Senate seat representing one of the most ethnically divided, Byzantine states in the country. Whatever else you say about it, that takes chutzpah.

But she may find that she has tested the tolerance of the American public one time too many. The role of first lady is not a constitutional office, but it always has been a very important part of the institutional glue that holds this country together. First ladies, whether they have been revered or reviled, are part of our history.

Carl Sferrazza Anthony, author of the two-volume history of the first ladies, put it this way: "They too have known they were not just the wives of public officials, but something quite different: Julia called herself `Mrs. President Tyler.' " Abigail Adams, he noted, wrote letters in which she examined her role.

"This institution, albeit unofficial, has its own history and roots," he continued. "(Subsequent generations) of first ladies may not realize it, but they have inherited certain customs indigenous only to their role, stemming back to Martha. To deny them having had a `heritage' consequently voids a nation's full understanding of its unique culture."

First ladies are an integral part of the presidency, wielding power behind the scenes and helping to shape the public perception of their husband's administration. Of our modern first ladies, Eleanor Roosevelt was the most politically active, and Mamie Eisenhower probably the least. But by the end of her last year, Mrs. Eisenhower had flown 32,000 miles to fulfill first lady duties, and her activities were being beamed into the nation's living rooms. "The First Ladyship had taken wing with the `Jet Age,' " writes Anthony. "Now it would soar."

Hillary R. has spoken often of her admiration for Eleanor Roosevelt, who was certainly the moral conscience of her husband's administration and, arguably, of the country. She was the first real spark of hope that kindled what would later be known as the civil rights movement. She was bitterly criticized by the conservative establishment, but as political as Mrs. Roosevelt was, she never abdicated her traditional role to run for political office.

Mrs. Clinton and Mrs. Roosevelt live in two very different eras in terms of the roles of women. Mrs. Clinton is widely admired among feminists for her activism on behalf of women's rights and girls' education. She is the first first lady to have had a professional career prior to moving into the White House. Once there, she and her husband broke another precedent when she was put in charge of the commission to reform the health care system. At that, she not only failed, she failed disastrously: No comprehensible plan emerged, the American public was turned off, and the opportunity to create a national health care system was wasted. For a while, Mrs. Clinton retreated from any public policy role, then went abroad and talked about microenterprise and the importance of educating girls -- all safe areas of expertise for a first lady. Her popularity moved back up.

It soared when she did the most traditional of things, which was to stand by her man when he finally admitted cheating on her with Monica Lewinsky. Their partnership-marriage held together through President Clinton's horrendously public humiliation. But if their marriage was strained, so was the country's tolerance. Just who do these people think they are that they can put the country through this kind of emotional ordeal?

New Yorkers are viewing Hillary R.'s candidacy with suspicion, and rightly so: She's bought a house in Westchester, but she doesn't live in it. They're accusing her of being a carpetbagger before she's got her own carpets down. Her trial-balloon campaign soared at the beginning as if it was powered by helium, but that balloon has been punctured by realities that exist only in New York. So far, Mrs. Clinton has offended the Puerto Rican community and the Jewish community. Not good for starters in New York.

Faced with mounting criticism that she was not serious about running, Clinton announced last week that she was going to move to the state and campaign "as vigorously as possible." She and her husband will have a commuter marriage. The net effect is that she is going to leave the White House at the beginning of next year and devote herself to one of the most arduous, expensive and brutal Senate campaigns there will be. It is a political separation, if not a marital separation, and there will be the perception in some uncharitable corners that she is using this Senate campaign to back-door her way out of her marriage.

Her bid is no sure shot. She's likely to face New York Mayor Rudolph W. Giuliani, who has been called the greatest mayor New York City has ever had by the hyperbolic Donald Trump. Giuliani made the city safer for its residents than it's been in a long time. That counts for a lot.

Hillary R. has always been as ambitious as her husband. She's a terrific speaker, warm in person, and very gracious. She masters her material and rarely refers to notes. She will be an effective campaigner, and by abdicating her position as first lady she will be able to separate her politics from those of the president. But will voters accept yet one more precedent-shattering move by the Clintons, or will they hold this against her?

From Martha Washington to Hillary R., first ladies have been woven into the tapestry of American history. When crisis has overtaken a president, they've risen to the occasion. They are ballast in the ship of state. Mrs. Clinton is turning her back on that and on the very great honor the American people bestowed upon her when they made her husband president. It may not put her in the Senate, but she's sure going to be one for the history books.