Sen. Hillary Rodham Clinton, D-N.Y., addresses the Democratic National Convention in Denver. Clinton urged her supporters to move forward from her own historic campaign and throw their support to Sen. Barack Obama of Illinois.

Denver ? Sen. Hillary Clinton on Tuesday turned the second day of the Democratic National Convention into a celebration of her historic presidential campaign as a breakthrough for women, but she left no doubt that she’s solidly behind Barack Obama as her party’s nominee for the presidency.

After a video tribute to her long campaign against Obama for the nomination, Clinton walked onstage, introduced by her daughter, Chelsea, who called her “my hero and my mother.” Together they faced a sea of waving white signs scrawled with the word “Hillary” in blue.

Clinton told everyone unequivocally: “I’m here tonight as a proud mother, as a proud Democrat, as a proud senator from New York, a proud American and a proud supporter of Barack Obama. … Whether you voted for me or voted for Barack, the time is now to unite as a single party with a single purpose. We are on the same team, and none of us can sit on the sidelines.”

“No way. No how. No McCain,” she said as people roared. “Barack Obama is my candidate. And he must be our president.”

She thanked her supporters, whom she called “my champions – my sisterhood of the traveling pantsuits. You never gave in. You never gave up. And together we made history.”

Her speech gave the convention an emotional lift after a desultory second day of speeches by a parade of Democratic politicians.

Shannon DeRubens, a Seattle stay-at-home mother, called Clinton’s speech “amazing” and said it helped move her closer to embracing Obama. “I am still looking for the Obama experience Thursday night,” she said, when the Illinois senator will make his acceptance speech.

Linda Mitchell, the president of the Washington state National Women’s Political Caucus, agreed. “We knew what was coming in Senator Clinton’s speech,” Mitchell said. “Did it bring closure? No. We need to save some tears for tomorrow,” when former President Bill Clinton will speak.

As Clinton moved into the heart of her message Tuesday night, women young and old sat intently, as though they were seeing the coda to a chapter of American history. Bill Clinton watched from a club level box, his hands in a triangle over his mouth, a serious look on his face.

Hillary Clinton clasped her hands, as though in prayer, as she talked about the fight for “an America defined by deep and meaningful equality, from civil rights to labor rights, from women’s rights to gay rights.”

Obama watched the speech in Billings, Mont., with Eran Thompson, 32, a field organizer for the Montana campaign, and his wife, Carlee.

After Clinton spoke, Obama said: “That was excellent. That was a strong speech. She made the case for why we’re going to be unified in November and why we’re going to win this election. I thought she was outstanding.”

Obama heard Hillary Clinton tie his White House bid to her husband’s presidency in her address.

Obama, his former rival said, will “meet the global challenges of our time. Democrats know how to do this,” she said. “As I recall, President Clinton and the Democrats did it before. And President Obama and the Democrats will do it again.”

Up went vertical blue signs that said “Unity.” From the Alaska delegation in one corner to South Carolina in the other, they bobbed.

“We are Americans,” Clinton told them. “We’re not big on quitting. But remember, before we can keep going, we’ve got to get going by electing Barack Obama the next president of the United States.”