DES MOINES, Iowa - Already they have interrupted Michele Bachmann and drawn a withering putdown from Newt Gingrich as "all noise, no thought."

Now, to the dismay of Iowa Republicans, Occupy activists in Des Moines are vowing to expand their protests as GOP presidential candidates converge on the state that speaks first in the race for the party's presidential nomination.

"The 99 percent have woken up and we're not going to take it anymore," Occupy activist Stephen Toothman, of Des Moines, said as an advance guard met Tuesday to decide which candidates to target in the coming week.

Hundreds of Occupy activists from at least 10 states were expected to participate in a "People's Caucus" near the Capitol to plot activities leading up to the Jan. 3 caucuses. The activists promise to interrupt candidates at events and camp out at their Iowa campaign offices. They say they want to change the political dialogue, but critics fear their tactics could tarnish Iowa's reputation for civil political discourse ahead of the contest. Activists say mass arrests are possible.

They planned to break up into preference groups based on which candidates they want to target and present a list of grievances to.

Organizers are encouraging activists who live in Iowa to show up on caucus night and vote "no preference" as a protest, but they say they have no plans to interfere with the voting itself. Nonetheless, state Republican Party officials have instructed precinct leaders to report any disruption to police and the party.

Iowa GOP Chairman Matt Strawn criticized Occupy activists for targeting the caucuses, which have long been held up as a model of democracy in which citizens in the months leading up to the event can directly question candidates, then gather with their neighbors on caucus night. Strawn said he worried that most of the problems would be caused by out-of-staters.

"It would be an absolute shame if outside agitators ruin the Iowa caucus experience," he said.

Occupy activists, who came from as far away as New York and Seattle, said the caucuses were largely meaningless because the parties and candidates were overly influenced by wealthy, special interests that led them to ignore key issues.

Ivan Burghart, an activist from St. Louis who mingled with others at the group's Des Moines headquarters, said: "The caucuses are really a statement as to where the nation is as a whole. I think this occupation is really a statement that they are dissatisfied with all the choices that we've been given."

Occupy Des Moines organizer Jess Mazour, 24, said protesters wanted candidates to address issues ranging from campaign-finance reform to college debt to the home-foreclosure crisis. She said the weeklong set of actions marked a new phase for the nationwide Occupy movement.

The group insists it will practice nonviolence, and activists were going through civil-disobedience training Tuesday. Still, police fear that scuffles could break out between frustrated candidates' supporters and protesters at events.