Retired Army Gen. Wesley Clark (search) has told friends he is likely to become the 10th Democratic presidential candidate, a move that could shake up the crowded field just four months before the first ballots are cast.

Clark, 58, has not made a final decision, but the Arkansas resident is aggressively recruiting campaign staff and plans to announce his intentions next week, friends and party officials said on condition of anonymity.

He could still put the brakes on a campaign, they said.

Clark confirmed that he was putting a campaign plan together but chalked it up to the type of "parallel planning" common in the military. "If you want to find out whether you're going to go ahead, you have to have financial resources and you have to have staff available," he told The Associated Press.

While mulling his options, Clark has met with several presidential contenders who covet his endorsement and might consider him for a vice presidential slot. He met Saturday with former Vermont Gov. Howard Dean (search), who said it is too soon to talk about political alliances.

"There is a lot of vetting that would have to be done before you would have those kinds of discussions," Dean said when asked whether he had discussed the vice presidency with Clark.

A senior adviser to another Democratic contender described Clark's talks with his candidate as "almost an audition for the vice presidential sweepstakes."

If Clark were to enter the race, it would be to win the nomination and not simply position himself for the No. 2 slot, friends said.

Clark has a resume that unnerves potential rivals -- Rhodes scholar, first in his 1966 class at West Point, White House fellow, head of the U.S. Southern Command and NATO commander during the 1999 campaign in Kosovo.

A Clark White House bid would grab the political spotlight and undercut the strengths of several in the nine-way Democratic race.

Dean's effort to solidify his front-runner status might suffer from the distraction of a Clark candidacy. Sen. John Kerry of Massachusetts would no longer be the race's only decorated combat veteran. Sens. John Edwards of North Carolina and Bob Graham of Florida would face another Southerner.

"He's all potential and upside," said Democratic strategist Donna Brazile. "The question will be whether he could put together the organization so late."

A senior Democratic Party strategist said Clark told him this week that he was "90 percent sure" he would run. Asked what would hold him back, Clark had no answer, according to the official, who also said Clark didn't seem to have answers to key questions about organizing a race.

Two acquaintances of Clark said he has told him he is likely to run, and the only thing stopping him is a last-minute change of heart or realization that he can't get an organization ready.

An Internet-fueled draft-Clark movement has developed the seeds of a campaign and more than $1 million in pledges. Dean, who also has used the Internet as an organizational tool, has said Clark would have an immediate impact on the race.

The American Federation of State, County and Municipal Employees (search) has postponed its endorsement -- once expected to go to Kerry -- to give Clark a month to prove himself.

Senior party leaders say Clark or his advisers have contacted several prominent Democrats in the last few days about jobs in the campaign should he take the plunge. Among them are Mark Fabiani, who ran Al Gore's communications team in the 2000 campaign.

"He's asked me to give him some advice on a variety of campaign issues this week, which I am doing," said Fabiani, who indicated he would consider working for Clark should he run. "He's a very impressive man and I think he would be a powerful candidate."

Clark also asked John Weaver, a top strategist in the 2000 presidential campaign of Republican Sen. John McCain of Arizona, to manage his campaign. Weaver said he declined because of health problems.

Clark disputed Weaver's characterization. "I was very impressed with John Weaver," he said. "There was never a firm offer made."

If he enters the race, Clark would enjoy the support of at least two longtime associates of former President Clinton -- Skip Rutherford and Bruce Lindsey, both of Arkansas. Clinton has spoken glowingly of Clark, but he has not taken sides in the nomination fight.

Clark believes his four-star military service would counter Bush's political advantage as a wartime commander in chief, friends say. The retired general has been critical of the Iraq war and Bush's postwar efforts, positions that would put him alongside Dean, Graham and Rep. Dennis Kucinich of Ohio as the most vocal anti-war candidates.

Dean has met four times with Clark. In the last several months, Clark talked to Kerry and Sen. Joe Lieberman of Connecticut, among other contenders.

Dean's campaign manager, Joe Trippi, and Clark's advisers also talked frequently. Officials familiar with the conversations say Dean has sought Clark's endorsement, but there has been no promises made about putting Clark on a potential Dean ticket.

Clark is scheduled to deliver a speech at the University of Iowa on Sept. 19, but he has said he'll make his decision before that. Officials say next week's announcement will likely be made in Little Rock, Ark.