Because she is Democratic National committeewoman from New York, Hazel Dukes undoubtedly knows that in four of the last five presidential elections her party has been badly beaten. She also undoubtedly knows the recurring doubts American voters have expressed during those years about the Democrats' national leadership: inability to define an overriding national interest distinct from the narrow interests of special constituencies; lack of tough, independent leadership; the perception that Democrats were no longer pioneers of change but protectors of the status quo.

Because she is also a board member of the NAACP, Hazel Dukes this week introduced New York Democratic Sen. Daniel Patrick Moynihan to that group's convention as someone who would certainly vote against the nomination of Judge Robert H. Bork to the Supreme Court. When she later learned that Moynihan would not say how he intended to vote on Bork, Hazel Dukes responded: ''I have the votes in New York to defeat him. When I get together with his staff in New York, I'll get what I want. It's strictly politics.''

Now, think just for a minute of what this means for the current plight of the Republicans. Here they are with an administration everywhere under investigation or suspicion and a president who looks to be the only living American with White House mess privileges who did not know how the contras were meeting their payrolls and loading their muskets. In November of last year the GOP lost the Senate and in November of next year they look to be a good bet to lose the White House. But wait: see if the Senate Democrats genuflect before the organized pressure groups on the nomination of Bork. A return to voter confidence and national leadership for the Democrats does not lie in a Senate filibuster of an able Supreme Court nominee.

In those last five presidential elections, the Democrats have won only 21 percent of the nation's electoral votes. One of the consequences of any party's being that noncompetitive for such an extended period is that the other party gets to nominate the members of the federal judiciary. And, except for when they are audible and palpable turkeys, those nominees are usually confirmed.

During the past 10 years, a lot of Democrats have revealed themselves as both unquestioning defenders of the status quo and anti-majoritarian snobs. There was a time, not too long ago, when Democrats genuinely welcomed huge Election-Day turnouts, confident that the more people who voted the better the party of the people would do. Now the preference seems to be for law clerks, not voters, to decide questions of public policy. That attitude is fundamentally anti-democratic.

The Bork nomination can surprise no one. In two national elections, Ronald Reagan carried 93 of 100 states while repeatedly amplifying his views on narrow construction and traditional values. Bork's credentials and his record entitle him to a prompt hearing and serious consideration. The arguments against his confirmation do not want for material or for eloquent advocates. But those Democrats who would prefer one day soon to propose nominees and ideas rather than simply to oppose them as they now do have to realize that the political power to initiate lies not in the approving press releases of pressure groups but in the White House.

And what about Sen. Moynihan, with a 100 percent pro-NAACP voting record? Now if he conscientiously studies the record and sincerely opposes the Bork nomination, Moynihan is guaranteed that his 1988 opponent, thanks to Hazel Dukes, will be able to accuse the Democrat of buckling under to interest-group extortion.

To win the White House, the Democrats must nominate a leader with vision who is independent, tough and can effectively define the national interest. To many thoughtful Democrats, Joe Biden of Delaware, the chairman of the Senate Judiciary Committee, looked like he could be that leader. But by seeming in the Bork nomination fight to be the prisoner or the patsy of liberal pressure groups, neither Biden nor anyone else will fill that bill of leadership for change.