Richardson's plan would immediately withdraw all U.S. forces from Iraq and focus on diplomacy.
COLUMBIA, South Carolina (CNN) – One of New Mexico Gov. Bill Richardson's South Carolina advisers is leaving the presidential campaign because of Richardson's Iraq plan and signing up with Sen. Joe Biden.
Citing Richardson's liberal stance on Iraq, which would immediately remove all U.S. forces from Iraq, the campaign's South Carolina state co-chair Fletcher Smith said Biden's plan to divide Iraq into three federal regions is a more responsible plan.
"To me it's the only way this problem is going to be resolved," Smith said in a phone interview Saturday morning. "Right now we have a quicksand of a civil war, and I don't believe we can just pull out precipitously in a six month period of time without jeopardizing our interests in the region. We don't need another evacuation that we had in Vietnam."
Smith serves in the South Carolina House of Representatives and is a member of the South Carolina Legislative Black Caucus. Smith has been the co-chair of Richardson's South Carolina steering committee since July.
He said he had spoken with Richardson and his staff.
Smith said he did not consider joining any other Democratic campaign besides Biden's, and noted he was drawn to Biden because he is an Irish-American.
"Irish-Americans faced the same problems African-Americans have faced in this country," Smith said.
The Richardson campaign did not comment on Smith, but defended the Governor's Iraq plan.
"Governor Richardson has a real plan to get our troops out of Iraq," said Richardson spokesman Lachlan McIntosh. "He's the only major candidate who will get all of our troops out quickly and leave no residual forces whatsoever. Our men and women are currently targets in Iraq. The longer we stay, the more will die."
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– CNN South Carolina Producer Peter Hamby