There is nothing so important in politics — or indeed in marketing of any sort — than name recognition. Offered a list of candidates by pollsters, voters tend to say they like the candidates whose names they know. Familiarity is the main reason Hillary Clinton started as the Democratic frontrunner. It is why John Edwards began in third place. It is why Rudy Giuliani and Fred Thompson cast such a long shadow over their rivals. It is why Mike Huckabee, in every other way the perfect candidate for frustrated social conservatives, cannot get traction.

But is it possible to be too well known? Before she set out on her White House run, everything about Mrs. Clinton was so familiar that people had already made up their minds about her. For every person saying they would definitely vote for her there was a second insisting that under no circumstances would they support her.

It is in the large number of negative opinions of Mrs. Clinton that Karl Rove holds out hope that the election next year is not a foregone conclusion. If all those who dislike Mrs. Clinton vote for the Republican candidate, voila, she loses.

However, Mrs. Clinton is so well known that something else may be at play here. Eight years of being First Lady to Bill Clinton, with all that that entails, has provided so much information about her marriage, her temper, her abilities, her daughter, and most everything about her, that there is, surely, little left to find out.

Some interesting figures about Hillary Clinton’s chances of election were published in the Wall Street Journal on Monday, though they were not a traditional opinion poll. They were sales figures of books about Mrs. Clinton.

Some years ago, expecting a Clinton presidential run, publishers commissioned authors to trawl through her life and come up with something fresh, in time for the preprimaries season. The result has been, if not quite an avalanche, at least a landslide of biographies about Mrs. Clinton, which has meant in practice books about the Clinton marriage.

What is surprising is not the extent of the revelations about the Clintons — nothing much new has emerged — but how few books have been sold. Quoting Nielsen BookScan, the industry standard on book sales, the Journal reports that of the 275,000 copies Knopf printed of Carl Bernstein’s “A Woman in Charge,” published in the summer, only 57,000, or about a fifth, have so far been sold. Of the 175,000 copies of “Her Way,” a caustic reappraisal of Mrs. Clinton’s life by Jeff Gerth and Don Van Natta, published by Little, Brown in the summer, just 19,000, or a little over a tenth, have been sold.

It seems that we know quite enough about Mrs. Clinton already to help us come to our judgment and that further evidence is not needed. This poses a problem for the Clinton campaign: if people have already made up their minds about Mrs. Clinton, what can be done to change the opinions of those who have a poor estimate of her? The short answer is, not much.

But our over-familiarity with Mrs. Clinton also offers her campaign an advantage: if everyone already knows everything about the Clintons’ marriage, and the scandals that dogged them from Little Rock to the White House, there is little chance that she can be Swiftboated. If even the mighty president slayer Carl Bernstein cannot find anything bad to say about her that we do not already know, what chance that a Republican dirty tricks expert can come up with something new to devastate her campaign?

The short answer is, again, not much, so long as the dirty tricksters stick to the facts. What John Kerry discovered, however, is that in the heat of a presidential campaign “the facts” and “the truth” about events that took place long ago and far away were difficult to establish and defend. If there is a deliberate effort to besmirch by providing misleading facts and misinformation, even Mrs. Clinton may find herself vulnerable to attack.

More troubling for Mrs. Clinton, perhaps, is that familiarity breeds if not contempt then at least antipathy. The Hillary books are gathering dust on the shelves of Barnes & Noble because not enough people are prepared to sit for hours wading through the well established elements of Mrs. Clinton’s life.

Those too young to be paying attention to the Clintons the first time appear understandably reluctant to catch up on Whitewater, the White House travel office, Vince Foster, the Arkansas state troopers, and Monica. And who can blame them.

Which provides the ultimate dilemma for Mrs. Clinton. What voters must decide is whether they can bring themselves to call up the past and invite into the White House and their television screens a sequel to the first eight Clinton years. As the stand-up comics tell us, nostalgia isn’t what it used to be. And eight more years of the Clinton soap opera may prove too much to bear.

nwapshott@nysun.com