Supporters of Democratic presidential candidate Hillary Clinton rally outside the Iowa Democratic Wing Ding in Clear Lake, Iowa on Aug. 14, 2015. 
Photo by Win McNamee/AP

Dueling chants prepare Iowa for the annual Wing Ding

Updated

CLEAR LAKE, Iowa – Five hours before four Democratic presidential candidates were slated to take the stage here and speak, their grassroots supporters were shouting themselves hoarse. 

Supporters of former Maryland Gov. Martin O’Malley – the first on site outside the Surf Ballroom – stood chanting and cheering armed with signs and sunblock in the blistering heat, when a large, raucous team of Hillary Clinton supporters rounded the corner.

“I believe in Hillary! I believe in Hillary!” they roared, inciting a chant duel with the O’Malley team who fired back with cheers of their own, “O’Malley! O’Malley! O’Malley!”

The boisterous hordes were just a preview of Friday night’s Iowa Democratic Wing Ding, where 1,800 Iowans and 160 reporters are expected to attend. It’s a sold-out party gathering where caucus goers from this crucial first-in-the-nation voting state will crowd a historic ballroom – the site of Buddy Holly’s last show – to hear from the major Democratic contenders: Clinton, O’Malley, Vermont Sen. Bernie Sanders, and former Rhode Island Gov. Lincoln Chaffee.

The event will be particularly crucial for Sanders, who has surged into first place in some New Hampshire polls but is lagging Clinton in Iowa. The self-described socialist has drawn huge crowds in coastal urban areas but has yet to demonstrate that he can convert that energy into actual votes. 

After an embarrassing third-place finish in the Iowa caucuses in 2008, Clinton this time seems prepared for a fight and has a strong grassroots operation up and humming. She scored a key endorsement on Thursday, with the state’s former Democratic senator and progressive champion, Tom Harkin penning an editorial in The Des Moines Register announcing his support. Harkin called Clinton “a fighter who has a record of getting things done and the vision for the future that will build on the progress we’ve made.”

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The fundraiser benefits 23 county’s Democratic parties; it’s largely a grassroots event, organizers told msnbc, with a more down-home feel – attendees paid around $30 for the event where they’ll feast on wings and many will end up sitting on the floor.

The event takes place in Republican Rep. Steve King’s district, a decidedly conservative part of the state. The controversial lawmaker is one of the most politically outspoken opponents of immigration reform and suggested recently that the Supreme Court in its marriage equality ruling legalized marriage to lawnmowers.

Bernie Sanders, Hillary Clinton, Iowa, Lincoln Chafee and Martin O'Malley

Dueling chants prepare Iowa for the annual Wing Ding

Updated