Heidi M. Przybyla

USA TODAY

AMES, Iowa — If Bernie Sanders loses Iowa's caucuses on Monday, he may be a victim of his own success.

Like then-senator Barack Obama in 2008, Sanders is powered by a groundswell of enthusiasm among young voters who view him as an incorruptible populist fighter. Unlike Obama, his campaign was caught off guard by massive crowds early in the cycle and was late in channeling them into a grass-roots organization, officials concede.

While the Sanders campaign now says it has an activist army spreading the word on social media, at rallies and even campus bars, it may not be enough to gin up the participation levels necessary to overcome Hillary Clinton’s statewide advantages among reliable Democratic caucusgoers. For her part, Clinton is also far more organized than she was when she lost in 2008 to Obama.

Brandon Holdgrafer, a 20-year-old physiology major, is a good example of Sanders’ challenge.

In between sips of coffee at a Starbucks in Ames, Iowa, Holdgrafer said he feels “really strongly” that Sanders is what the country needs and that he “cares about people.”

Clinton holds on to small lead over Sanders

Even so, he will not caucus for Sanders. “I’d love to be supportive of him,” said Holdgrafer. “I can’t, I have class,” he said. The same was true for Cesar Victor, a 22-year-old industrial design major, who also has a “time issue.”

Holdgrafer said Sanders probably has enough support to succeed without him.

The problem for Sanders is that Holdgrafer may be wrong: Sanders does need him.

Iowa State University is situated in Story County, one of three college counties that are must-wins for Sanders, according to former Iowa senator Tom Harkin, who is supporting Clinton. Clinton lost Story in 2008 with just 23% backing, to Obama’s 40%.

According to the Iowa secretary of state, new voter statewide registrations showed sizable jumps in the two months leading up to the 2008 caucus, increases that aren’t as significant this time, according to spokesman Kevin Hall. And according to a new Des Moines Register poll, Sanders isn't drawing in as many new voters as Obama did. In 2008, 60% of caucusgoers were participating for the first time, to just 34% now. Overall, Clinton has a 3-point lead over Sanders.

Turnout in Iowa has been wildly unpredictable, from a low of about 30,000 in 1992, though that race was not contested, to a high of nearly 240,000 in 2008, according to an analysis by Monmouth University.

The Iowa caucuses: An accident of history

Its recent poll, which screened for likely caucusgoers, predicted about 110,000 Democratic voters on Monday. The higher the turnout, the more Sanders gains.

“We will lose the caucus on Monday night if there is a low voter turnout,” Sanders warned at a campaign rally over the weekend.

Even if Sanders can get young voters to show up, their support might be too concentrated in counties like Story. Democratic candidates win in Iowa by collecting delegates in every county instead of by running up the popular vote.

Iowa Caucuses History | DesMoinesRegister.com

“It’s tough to really fault anyone at the Sanders campaign because they were drinking out of a fire hose for a long time” with few staff on the ground, said Brad Anderson, Obama’s Iowa 2012 state director who is supporting Clinton.

“They just missed out on a lot of time,” said Norm Sterzenbach, who was the Iowa Democratic Party’s Caucus director in 2008.

“They’re being driven primarily by enthusiasm instead of tactics, whereas Obama had both,” said Sterzenbach, who is unaligned.

If Sanders loses Iowa, he still stands a good chance of beating Clinton in New Hampshire, the first primary state that borders his home state of Vermont. Yet the math to win the amount of delegates needed to clinch the nomination becomes very difficult for Sanders as the race moves to a belt of March 1 Southern states where Clinton has decisive leads powered by black voters.

Clinton flashbacks to 2008 may end after Iowa

Rania Batrice, Sanders’ Iowa communications director, said tightening poll numbers are evidence the campaign has overcome its early challenges.

“It was a slower start than maybe other folks are used to,” she said. “The numbers haven’t shifted by accident,” she said. “Our field team is second to none.”

The campaign is hoping significant numbers of new voters will register on caucus night. They’re also confident that, under the rules, they will benefit from wooing the supporters of former Maryland governor Martin O’Malley, who is polling in single digits.

Clinton, Sanders to compete for O'Malley backers

Other Democrats say they’re seeing, anecdotally, what the secretary of state’s numbers suggest about a potentially lower voter turnout than in 2008. Barb Hildebrandt, a 49-year-old precinct captain from a heavily Democratic area in Des Moines, said she’s been a chair for 20 years.

“We’d never seen most of the people who came out (door knocking) for Obama, we hadn’t seen them in our churches or neighborhood meetings,” said Hildebrandt, who is supporting Clinton. “That’s not happening this time,” she said.

What’s more, Clinton deployed paid staff to the state far earlier, with dozens in place as early as April. Sanders was still operating with about three staff members over the summer.

Beyond the challenge of herding young voters to their local precincts on caucus night, there are other pitfalls to depending on them in Iowa.

“They’ve got precinct captains who haven’t been to a caucus before,” said Jeff Link, a former Obama aide who is supporting Clinton but not working for her. “There’s a lot of horse trading that goes on” and “the Clinton people don’t really have to train their captains,” who are more seasoned, said Link. Caucus meetings can last several hours and rely on sometimes quirky rules for determining whether a candidate wins delegates.

David Karayof, a 25-year-old student and precinct captain, has never caucused.

“It’s a very legitimate issue that a lot of people have been saying stuff like ‘I have work or I have class.' I actually got in trouble for going to a Bernie rally instead of going to class,” he said.

Even so, he said, “I think we’re going to be pleasantly surprised.”

It will be possible to tell relatively early in the night whether Sanders can deliver the numbers needed to win, said Link.

“We’ll have a sense of it as soon as people start checking in,” said Link. “If there’s a really long line it’s going to be good for Sanders. If it’s a medium-sized line and you know a lot of the people it’s going to be good for Clinton.”

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