Wesley Clark (search) conceded Monday he's the underdog heading into Southern primaries on Tuesday but toughened his criticism of President Bush while offering voters what he said was the clearest of choices in picking Bush's Democratic opponent.

"This is the time for the voters of Tennessee to decide," Clark said. "You've got a front-runner, you've got a good lawyer and you've got an underdog. I'm the underdog."

Polls show Clark trailing both front-runner John Kerry (search) and fellow Southerner John Edwards (search), a former trial lawyer, in elections scheduled Tuesday in Tennessee and Virginia. Twin third-place showings would rock his campaign. He argues he's the best candidate to compete in the South, but he has yet to demonstrate power in the region.

"You've got a choice in this race. You've got a lawyer ... he's a wonderful man," Clark said. "You've got a man who has spent his life in the Senate ... and you've got somebody who has spent his whole life out there rolling up his sleeves, working with people, building teams, making things happen."

Clark was putting the finishing touches on his Tennessee campaign by stumping through six cities before ending his day in Nashville with country music star Jamie O'Neal. Along the way he met with backers at blues legend B.B. King's club in Memphis, hopping onto the stage in front of a band.

"If you put me on third base in this election, I'll make it all the way home," Clark said. While the band played another driving tune, Clark stayed on stage swaying to the music and pumping his fists in the air, smiling broadly.

Earlier Monday, Clark criticized Bush's handling of the war in Iraq in some of the sharpest language to date.

"He cannot get away with taking this country to a war we didn't have to fight," he said. "That's like one of the greatest crimes you could ever, or greatest mistakes you could ever make."

Clark was pressed at one stop by a man who described himself as a Vietnam-era veteran on whether Clark would make an issue of questions that have been raised about Bush's military service during that era.

"I know that all of the charges about what he did or didn't do 30 years ago are offensive because all of us who did serve know that you had a job to do and you're supposed to be there," Clark said.

Bush served in the Texas Air National Guard during the Vietnam era, but some have raised questions about whether he actually served all of his enlistment. Bush says he was honorably discharged and that should answer questions.

Clark sought to use the issue to underscore his credibility as a decorated veteran to criticize Bush's handling of the war.

"There's more and more discussion about this, it is an issue," he said. "As a veteran, I spent 34 years in, and I am so offended he would use our armed services in that way."

Clark has vowed to press forward, regardless of his showing in Tennessee and Virginia on Tuesday, contending that only a decorated military officer can challenge a wartime president.

"I'm the best person to hold George W. Bush accountable for what he's done on national security and what he's failed to do to keep the country safe," he said.

Clark got a haircut in Dyersburg, Tenn., from Raymond Criswell, 85, who has operated the same shop since 1930. "People down here know how to cut hair," joked Clark, who paid for the $10 trim with a $20 bill. "Keep the change," he said.

An independent, Criswell said he was inclined to vote for Clark.