All Democrats understand that party unity will be necessary for their candidate to win the presidential election.

Thus, it fell to Sen. Hillary Rodham Clinton during her speech Tuesday night at the Democratic National Convention to rally her supporters behind Sen. Barack Obama, the party's candidate.

In the primaries, the New York senator received millions of votes, won many states and finished strong. But she did not win, to the dismay of many supporters, particularly those who pinned their hopes on Sen. Clinton becoming America's first woman president.

Yet laying aside her disappointment Tuesday in Denver, Sen. Clinton rose to the task of encouraging her followers to get behind Sen. Obama. This was necessary because polls have shown about half of her supporters were either undecided about Mr. Obama, thinking about voting for Republican hopeful Sen. John McCain or perhaps not voting at all.

It is one thing to know what has to be done and another to do it well. Sen. Clinton did it well. She gave a passionate, humorous and thoughtful speech in support of Mr. Obama.

"My friends, it is time to take back the country we love. Whether you voted for me, or voted for Barack, the time is now to unite as a single party with a single purpose," said the New York senator. "I haven't spent the past 35 years in the trenches advocating for children, campaigning for universal health care, helping parents balance work and family, and fighting for women's rights at home and around the world to see another Republican in the White House squander the promise of our country and the hopes of our people."

She continued: "And you haven't worked so hard over the last 18 months, or endured the last eight years, to suffer through more failed leadership. No way, no how, no McCain. Barack Obama is my candidate. And he must be our president."

Mrs. Clinton made history by nearly becoming the first woman to win a presidential nomination from a major party. On Tuesday, she had to show unwavering support for Sen. Obama, thank the more than 18 million voters who backed her and ask them to unite behind Mr. Obama.

She did a masterful job.