DES MOINES -- In Sen. Barack Obama's Iowa headquarters, young staff members sit at computers, analyzing online voter data and targeting potential backers. They zip one e-mail to an undecided voter and zap a different message to a firm supporter.
Depending on the voter, they follow with Facebook reminders, telephone calls, text messages and, most important, house visits. The effort will culminate in what state director Steve Hildebrand calls "the largest grass-roots volunteer operation that Iowa has ever seen."
Whether Hildebrand's boast proves true on Thursday, Obama's campaign has taken a markedly different approach to identifying its supporters and getting them to the caucuses than those of his two main opponents, Sen. Hillary Rodham Clinton of New York and former senator John Edwards of North Carolina.
With turnout likely to be decisive in a Democratic race that pollsters call a three-way tie, Obama (Ill.) has built an Election Day operation that combines an apparent edge in technology with the tried-and-true grunt work of a traditional Iowa campaign. Edwards and Clinton have also assembled formidable ground operations, with outside help from labor unions and political interest groups.
Edwards, who has been campaigning virtually nonstop since finishing second here four years ago, is depending on caucus veterans. Strategists for Obama and Clinton are counting on a record turnout, which means inducing caucus neophytes to gather on a cold January night.
The chances appear good that more Democrats will participate than ever before.
"It's more money, more staff, more TV, more of everything," said Jean Hessburg, a former executive director of Iowa's Democratic Party. "We had a record turnout in 2004. I'm sure we'll break it in 2008."
Obama began organizing in Iowa by deploying more staff members earlier to more counties and by building tracking mechanisms to identify and retain supporters. For example, the campaign mines data gathered online: Which petitions did people sign on the campaign Web site? Which e-mails have they answered?
If the Internet is like a big grocery store, Obama's aides made sure he appeared on every aisle. As some campaign workers built mailing lists and telephone trees according to political, professional and personal interests, others created the first groups and profiles on sites as varied as Eons, the MySpace for baby boomers, and LinkedIn, a site mostly for white-collar professionals.
They also used BlackPlanet.com, MiGente.com, AsianAve.com and GLEE.com -- the MySpace and Facebook for, respectively, the African American, Latino, Asian and gay online communities. They have posted more than 350 videos on his YouTube channel, twice as many as Clinton, and his videos have been viewed nearly twice as often as hers. Obama has more MySpace friends than any other Democratic candidate, and he lists more Facebook supporters than all other Democrats combined.
Looking ahead to caucus day, the campaign is setting up a "catch-all queue," in which caucus-goers could get an answer within minutes after texting a question such as "Where's my precinct in Des Moines?"
Four years ago, another Democrat, former Vermont governor Howard Dean, came into the Iowa caucuses as "the Internet candidate" and finished third, all but ending his candidacy. Obama's campaign flatly rejects that comparison, arguing that today's Web is vastly different, that Iowa is much more wired, that they have learned that electronic touches are only part of the picture.
"We don't think we could be any more different than the Dean campaign," said Hildebrand, a veteran political strategist. "We get everyone who signs up with us online to get involved in person. It's not just a computer-to-computer relationship -- it's a person-to-person relationship. This is Iowa, after all."
Unions have their own 2004 precedent to avoid. That year, then-Rep. Richard A. Gephardt (D-Mo.), who won the caucus in 1988, was considered a favorite because of his strong union backing. Instead, he finished behind Dean and his candidacy was also ended.
Chuck Rocha, national political director of the United Steelworkers of America, has spent much of the past six months in Iowa, directing labor volunteers for the Edwards campaign. Over the weekend, about 130 steelworkers were in Iowa, spending eight hours a day on union time, then working the rest of their long days directly for the Edwards staff.
This time, Rocha said, his members are targeting union members more, engaging them on their doorsteps and at the gates of 21 Iowa factories instead of just passing out leaflets. The outsiders concentrate on identifying Edwards supporters and urging undecideds to see him in action. "What they're saying to our members is, 'You have a voice that I don't have. Use it,' " said Edwards precinct captain John Campbell, a steelworker and an Iowan. "We learned from our mistakes that a caucus is a different critter."
Clinton's campaign has its own target group: female voters, including many who have never caucused. In one ambitious effort to expand her base, Clinton launched an effort to reach women -- especially over 65, under 30 or single -- registered as independents or as Democrats considered unlikely to caucus. She taped a call to them and told them to expect an envelope in the mail.
The packet, less political than other Clinton mail, included a card that said, "If you're itching for change, scratch here to win." Those who sent it back received a blue travel mug that said "I'm standing with Hillary." The campaign collected the names of thousands of potential supporters -- so many that it needed a tractor-trailer to haul all the mugs.
"This is a huge experiment," said Karen Hicks, a senior campaign adviser. "We have no idea if this will work or not."
For weeks, the Clinton campaign has been doing much hand-holding of its newest recruits, pairing them with experienced caucusgoers to boost their confidence and inspire them to show up.
Along the way, the campaign has had considerable help from its union supporters. Emily's List, the women's political fundraising group, spent more than $400,000 to design an elaborate marketing program aimed at Iowa women. Strategists identified a large subset who described themselves as predisposed to support Clinton and having a six in 10 chance of caucusing.
"We realized it wasn't that we needed to spend our time building the support in Iowa for Hillary -- we just needed to turn out the support that she had," said Emily's List spokeswoman Ramona Oliver. "We looked at why they wouldn't go -- what were the barriers?"
The strategists found that many women simply found the caucuses confusing and intimidating, so they took several steps to counter that. At the same time, Emily's List designed an online advertising strategy that popped up a link to its Web site every time a computer in Iowa searched Google or Yahoo using specific terms. Some of the search terms were politically oriented, such as "2008 caucuses." Others aimed at the presumed interests of Iowa women, such as "recipe," "stocking stuffer" and "post-Thanksgiving sales."
By the end of the week, about 20,000 visitors from 613 Iowa towns had clicked on the ads.
"We really were trying to get to women where they live," Oliver said.
The group decided not to send out-of-state volunteers to knock on doors in Iowa. "It just felt wrong," said Maren Hesla, director of the group's Women Vote program. Instead, Emily's List sent names of targeted women to the American Federation of Teachers, a Clinton supporter, which sent its own literature promoting her.
All the organizational work is just a prelude to what will happen the night of the caucuses, which won't even begin until 6:30 p.m. Anything from bad weather to a sick child could prevent someone from leaving home, and that's why campaigns have been urging Iowans for months to bond with like-minded supporters at barbecues, house parties and mock caucuses. And that's why the ground armies are arranging rides and babysitters, and the candidates are returning again and again to Ottumwa, Davenport and Mason City.
The key of keys, Hildebrand said, is to knock on doors.
"Working the ground, going from house to house, talking to supporters and those leaning towards us and to undecided voters, is what we'll do all day Thursday," he said. "Nothing beats that door-to-door contact."