Sen. Barack Obama will hold a rally in Bangor on Saturday and former President Clinton will speak in Portland tonight as the campaigns of Obama and Sen. Hillary Rodham Clinton compete for votes in Maine’s Democratic caucuses on Sunday.

Obama will hold a “Stand for Change” rally at the Bangor Auditorium on Saturday afternoon, his campaign announced. The doors to the auditorium are set to open at 2:30 p.m.

The event is free and open to the public, but RSVP’s are encouraged. To RSVP, visit http://me.barackobama.com/bangor.

For security reasons, no bags, signs or banners are allowed.

Sen. Clinton’s campaign announced Wednesday that the former president will host a “Solutions for America” rally at 7:30 tonight at the Portland Exposition Building at 239 Park Ave. to share his wife’s message on how to change the country to improve life for America’s working families.

The event is free and open to the public, but those interested in attending are asked to RSVP at www.hillaryclinton.com/

portland.

At the State House this morning, Clinton’s campaign plans to trumpet her support by party notables, including Gov. John Baldacci.

Meanwhile, phones were ringing off the hook Wednesday at Maine Democratic Party headquarters in Augusta as officials attended to last-minute details in anticipation of this weekend’s party caucuses.

The source of much of the activity was absentee voters as Wednesday was the last day party members could file absentee ballots for the Feb. 10 caucuses. The state party’s executive director, Arden Manning, said he believed the wave of calls was indicative of the enthusiasm for the caucus.

“It’s been a busy day up here at Democratic Party headquarters. We’ve received more than 5,300 absentee ballots so far,” Manning said. “When you compare that to the 5,000 people who participated in the three-day Republican Party caucus last week, it shows there is a huge amount of energy in our party this year.”

Democrats from 420 Maine towns will caucus at 372 locations Sunday, Manning said. Most of the caucuses will take place in the afternoon. Manning said that a record-breaking 17,000 Democrats took part in the 2004 caucus and that he expected even more would attend this year’s caucuses.

“I think we’ll definitely match that,” Manning said.

Sens. Clinton and Obama are locked in a tight race to secure their party’s nomination and every delegate counts, Manning said.

“What happened last night [Super Tuesday] makes Maine very important,” he said. “I’m sure both campaigns will be working hard for delegates.”

As of Wednesday, Clinton had 1,024 delegates and Obama had 933. Maine has 24 delegates in play, just over 1 percent of the 2,025 needed to clinch the nomination.

Maine House Speaker Glenn Cummings of Portland, who supports Obama, echoed Manning’s sentiments.

“With the delegate vote so close, every delegate counts,” Cummings said.

Earlier in the campaign, Maine’s importance was largely written off because its caucuses were scheduled after Super Tuesday, when it was assumed a front-runner would be identified. But Clinton supporter Elizabeth Mitchell, the state Senate majority leader, said that’s all changed.

“Now that we’re into a battle for delegates, Maine’s in play,” said Mitchell of Vassalboro. “The battle’s going to go right on.”

Caucusing Democrats will select 3,556 delegates to the state convention to be held May 31-June 2 at the Augusta Civic Center. Manning explained that party members will gather at their caucus locations and separate into groups depending on which candidate they support. The delegates are selected proportionately, so the candidate with the most supporters attending the caucus will win the most delegates.

The number of delegates a community has available depends on its proportion of party members. In Belfast, for instance, 20 delegates will be up for grabs. Portland, Bangor, Augusta and Lewiston will send much larger contingents of delegates to the state convention.

Manning said the absentee ballots would be delivered to the various local communities and be included in the final tally for delegate selection. Under party rules the support of the delegates selected to represent the town committee on behalf of a specific candidate at the state convention is binding.

Once at the convention, the delegates will select delegates to represent them at the Democratic Party’s national convention in Denver. Those delegates also will be bound to a specific candidates.

“Bound delegates select bound delegates,” he said.

Maine will be represented by 34 delegates and four alternates at the national convention. Of those, 10 delegates will be “superdelegates” and will consist of party leaders such as Gov. John Baldacci, Reps. Tom Allen and Michael Michaud, former Gov. Kenneth Curtis and former Sen. George Mitchell.

Also on that list are party chairman John Kuntson, vice chairwoman Marianne Stevens, and National Committee members Sam Spencer and Rita Moran. Some of the superdelegates have been contacted by the Clinton and Obama campaigns looking for support, according to reports. Baldacci and Curtis have already endorsed Clinton.

Maine’s Democratic caucuses will follow Saturday’s in Louisiana, Nebraska, Washington and the U.S. Virgin Islands and come just ahead of Tuesday’s preference events in Virginia, Maryland and the District of Columbia.

Maine Republicans said Wednesday that presidential caucus ballots from nearly all participating towns have been counted, but the results remained unchanged since the weekend, when Mitt Romney emerged as the clear winner.

With votes counted from 96 percent of the towns holding caucuses, the former Massachusetts governor had 52 percent, leaving John McCain with 21 percent, Ron Paul with 18 percent and Mike Huckabee with 6 percent. Undecideds accounted for 2 percent of the votes.

The Associated Press contributed to this report.