DID HE GET WHIPLASH? LIEBERMAN SWITCHED PRINCIPLES ON A DIME.

Byline: CHRIS WEINKOPF

``THE Democratic Party is the party of diversity,'' one proud delegate boasted at the Staples Center last week.

A high-school social-studies teacher from Appleton, Wis., she wore a vest plastered with pins and stickers, including a red-and-white decal from the National Education Association, the nation's largest teachers union. Her party's tolerance, she explained, allows it to embrace Joe Lieberman as its No. 2 standard bearer, even though he has supported educational vouchers, which the NEA detests.

Besides, ``when Joe Lieberman has a chance,'' she added, ``I think he'll come around to our side.''

Democratic convention delegates are a cheerful, earnestly idealistic bunch. They wear their Uncle Sam hats with pride, and gladly turn themselves - for four days, anyway - into partisan pin cushions, with a button for every cause and candidate poking through their wardrobes.

These are the true believers. In their minds, there's nothing wrong with public education that more money wouldn't fix, Social Security looks like a wise retirement plan and Cuba's biggest problem is not Fidel Castro but the U.S. embargo.

Teachers made up 12 percent of their ranks, and not one of the dozen or so that I spoke to doubted the malleability of Lieberman. ``I think he'll come around,'' one member of the Utah delegation confidently predicted.

Members of the Congressional Black Caucus, which champions racial preferences as avidly as the NEA resists vouchers, seemed equally unconcerned with Lieberman's past opposition to affirmative action.

``I feel comfortable with him,'' said a CBC member from North Carolina. ``I think since he's joined the ticket, his thought process is going to come in line'' with party orthodoxy.

And it has. In the mere two weeks since Gore chose Lieberman as a running ate because of his ``new guard'' principles and moderation, the Connecticut senator has busily cemented his toes to the old-guard party line.

Politics corrupts, but not usually with such speed - it took Gore years to abandon his opposition to abortion and gun control. Lieberman is on pace to shatter all records for selling out, which was good news for the delegates.

He ditched school choice, which he had supported for years, almost as soon as Gore gave him the nod. The Wall Street Journal reports that shortly after Gore asked him to join the ticket, Lieberman put in a call to American Federation of Teachers President Sandra Feldman, assuring her that there would be no room for vouchers in a Gore-Lieberman administration.

Then, speaking before the Congressional Black Caucus on Tuesday, Lieberman declared, ``I have supported affirmative action, I do support affirmative action and I will support affirmative action.'' The crowd roared, seemingly forgiving his 1995 complaint that ''affirmative action is dividing us in ways its creators could never have intended,'' and that ``if you discriminate in favor of one group on the basis of race, you thereby discriminate against another group on the basis of race.''

Changes of heart, of course, come with the vice presidential territory.

George W. Bush's dad dropped his references to ``voodoo economics'' after becoming Ronald Reagan's running mate. Dick Cheney has more recently tried to distance himself from some unpopular votes he cast in the 1980s.

But Lieberman, by virtue of being ``the conscience of the Democratic Party,'' is held to a higher standard. At stake is his vaunted reputation, the key asset he brought to the Gore campaign. Putting the two men on the same ticket was supposed to make Gore seem more genuine, like Lieberman.

Instead, it has made Lieberman seem more opportunistic - like Gore.

On last week's Fox News on Sunday, Lieberman tried his hand at Clinton and Gore's infamous semantic games, saying that he favors ``affirmative action'' but opposes ``quotas.'' Host Tony Snow then asked what Lieberman thought about his party's use of race and gender quotas in selecting its convention delegates. ``Well,'' he replied, ``I like to think of that as an acceptable affirmative-action program.''

It depends on what your definition of the word ``quota'' is.

The true believers at the convention didn't seem to mind the back flips. They learned in 1992 that political obedience is often more important than ideological fidelity. Bill Clinton was never their soul mate, but he could be counted on to do their bidding.

They now have no reason to fear that Lieberman's conscience will impede their agenda. As one Indiana delegate reported after hearing the candidate's address to the CBC, ``I thought he did very well . . . he made me feel a little more comfortable.''

For the rest of the country, which had looked to Lieberman to bring a fresh face and new ideas to partisan politics, his sudden gravitation toward the old way of doing business is disconcerting. Lieberman might be no worse than the rest of the political class, but Americans had hoped that he would be better.

CAPTION(S):

Photo: (color) After saying he supports affirmative action, Joseph L ieberman won a pledge of support - and an embrace - Tuesday from Rep. Maxine Waters.

Charles Rex Arbogast/Associated Press