PHILADELPHIA — While Barack Obama supporters waved signs outside, hundreds of Hillary Clinton backers were dancing to Jesus Jones' "Right Here, Right Now" as CNN announced on the screens in the Park Hyatt Ballroom that she would win that state's Democratic primary.

The room soon broke out into chants of "Madam President" and "Yes She Can!"

"For me, this is the culmination of many years of hard work," said 21-year-old David Helfenbein, a student at the nearby University of Pennsylvania. "When I was 13, I started something called Kids for Hillary in New York, so I've been with her for a while. This is going to be a good night, a big night."

But not everyone was ready to call it a victory just because the senator from New York won the popular vote here in Pennsylvania.

"I'm more anxious to see how much she wins by, because that's more important," said 13-year-old Mia Sever, who came up from Washington, D.C., with her mom to campaign for Clinton. "For it to be substantial, she needs to have closer to a double-digit lead. Right now, she's ahead by 7 percent, but it has been going up and down."

As the night went on, and her margin of victory continued to fluctuate, the Democratic Party's heavy hitters weighed in.

"If you look at where this campaign was two weeks ago, she closed the gap and then it widened back out," said New Jersey Governor John Corzine, a Clinton supporter. "She's won in most places Democrats have to win to put together an electoral map that wins the presidency."

Around 10:20 p.m., Clinton took the stage with her husband, former President Bill Clinton, and daughter Chelsea by her side.

"Today in Pennsylvania, you made your voices heard," she said. "And because of you, the tide is turning. We were up against a formidable opponent who outspent us 3-to-1. He broke every spending record in this race trying to knock us out, but the people of Pennsylvania had other ideas."

The outspending theme made a few appearances Tuesday night (April 22), and in what may be a victory-speech first, the senator made a plea for donations to her cash-strapped campaign. "We can only keep winning if we can compete with an opponent who outspends us so massively. So I hope you'll go to HillaryClinton and show your support tonight," she said.

While money might be tight for the Clinton campaign, the vote count was high enough for a win. One big part of that victory was Democrats who made up their mind in the last week or even the last minute. Clinton won among those last-minute deciders 56 percent to Barack Obama's 43 percent, according to an exit poll released Tuesday by Edison Media and Mitofsky International. Some of those late deciders were even at the victory rally with the hard-core Hillary fans.

"Within the past week, I've been kind of vacillating," said Caroline Sachs, a 21-year-old college student. "But I made my decision for Hillary."

By the time the crowd had cleared out of the ballroom, Clinton was up 10 points, and the longtime Hillary supporters still in the ballroom to track her progress were reveling in the win.

"I've been with her all along," said 20-year-old Aaron Gottleib, who voted in his first presidential contest Tuesday. "She needed a big win, and she got a big win. It was huge, and it felt good voting for her."

Across town, Obama staffers and supporters gathered to watch the results at the Waterworks Restaurant and Lounge, where the prevailing them of the night was "Yeah, but ..."

Everyone from local staff members to volunteers to Obama supporters came out to watch the election results at the scenic lounge near downtown Philly.

People here expected a Clinton victory but were curious as to the margin, holding out hope that their work in Philly and across the state — canvassing door-to-door and working the phone bank — would defy the prognosticators. Obama ran a really grassroots campaign, particularly in Philadelphia, where "people you'd never expect to get involved got involved," said Kelly Lanier, 20, an Obama supporter and student who came to the party mainly to see something she'd never seen before.

People here were encouraged by that grassroots vibe, keeping in tune with Obama's proclamation Tuesday from Evansville, Indiana, that change came through the bottom up.

Manny Arevalo, the deputy director for Veterans for Obama (a group we featured last week), said that the efforts and support network they cultivated here "will really come into play during the general election in November." Like most here Tuesday, Arevalo accepted that Hillary had Pennsylvania in the bag, "but we closed the gap, and I'm encouraged by what happened across Pennsylvania with the grassroots effort."

He was also encouraged by youth participation. "We engaged young voters and brought them in early. Personally, whatever the final numbers are tonight, young people getting involved is a great thing. And they'll stay involved, I think."

It's no surprise that the Obama post-election rally was here in Philadelphia. He was expected to pull up to 80 percent of the vote in this city, and earlier in the day, the downtown streets were filled with people holding pro-Obama signs, street bands holding impromptu jam sessions, and honking cars showing their support for the Illinois senator.

Even though the election was called early in the night for Senator Clinton, the mood here was generally upbeat, with people confident that Obama could hold off Hillary's momentum. Two of Obama's biggest supporters in the state, Senators Patrick Murphy and Bob Casey, attended the gathering, with the baby-faced Murphy, an Iraq war veteran, telling the crowd that after closing the gap in this state from 33 percent, the fight wasn't over and that people are "fired up and ready to go."

Casey also thanked the tens of thousands of Obama volunteers statewide and said that pulling off Obama's message of "hope and change was not going to be easy."

So while Clinton added another state under her belt, Obama supporters in Philly cautioned, "Yeah, but ..."

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