The Democratic nomination for president will likely be decided by the subtle pulls of ego against duty that tug at the conscience of John Edwards. He manifestly can no longer win - but he helps Hillary Clinton if he stays in the race and boosts Barack Obama if he pulls out.

After a vigorous campaign, Edwards has fallen irreparably behind - the real race is now a grueling test of strength with Clinton. The contrast between the party's insensitive establishment and the determined voices of change couldn't be clearer.

Edwards divides the anti-Clinton vote - and so undermines the prospects for the changes that he so passionately demands in our government. By staying in, he's helping deliver the nomination to the person whom he has described as the defender of the status quo.

The votes already cast and the polls of coming primaries all tell the same story: Edwards can't win. After a dis- tant second-place finish in Iowa, he still had some basis for hope. But when he finished far back in New Hampshire, his chances for victory vanished.

Just how hopeless is his candidacy? Realclearpolitics.com's average of national polls has him in third place - with Clinton at 41 percent, Obama at 35 percent and Edwards at just 15 percent. Even in South Carolina (right next door to his home state), he's polling at only 15 percent to Obama's 42 percent and Clinton's 30 percent.

To date, Edwards has been a passionate and effective advocate of the need for change. His opposition to special-interest funding of our politics and his good example in refusing to take funds from political action committees both merit our praise and admiration.

But at this point, the practical impact of any support for Edwards is to help Clinton defeat Obama. Polling shows that the second choice of Edwards' followers is overwhelmingly Obama.

By staying in the race after he has lost any realistic chance of winning, Edwards is making it possible for Hillary to win and to bring with her precisely the policies he most opposes: dependence on special interests, a determination to maintain a presence in Iraq and a reversion to dynastic politics.

Edwards deserves a special place in our politics for his efforts to bring poverty to national attention and to revise national priorities to take account of the needs of the poor. But now it's time to read the writing on the wall and obey the verdict of history. It's time for Edwards to pull out.