Of course the supporters of the candidates are there. That's the idea. They are there to cheer on their candidates.
They're 'bussed in' Iowans.
http://www.washingtonpost.com/wp-dyn/content/article/2007/11/10/AR2007111001574.html?hpid=topnewsAn estimated 9,000 people attended the Jefferson-Jackson dinner, the largest crowd in the event's history.
The first competition among the campaigns began Friday evening with a "sign war," in which young staffers raced one another to commandeer wall space in the auditorium for their candidate's placards. As the auditorium began to fill with people, the candidates' supporters marched through the corridors chanting, beating drums and raising the noise to ear-piercing levels.
Hours before the dinner, Obama staged a boisterous rally that featured R&B singer John Legend and thousands of supporters wearing red T-shirts with the words "I'm fired up" on the front and "He's ready to go" on the back. Those are chants that Obama uses to close his stump speeches, and they have become a rallying cry for his army of volunteers. ....Clinton and Edwards countered Obama's Legend concert with celebrities of their own: entertainment impresario Quincy Jones was here for Clinton, and country star Ralph Stanley performed on behalf of Edwards.
And Clinton supporters showcased their own T-shirt brigade, parading through the Veterans Auditorium and Hy-Vee Hall complex wearing yellow shirts that said "Turn up the heat" on the front and "Turn the country around" on the back.
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