ATLANTA --- Lt. Gov. Casey Cagle fought back tears Wednesday as he reluctantly dropped out of the race for governor, saying he has a degenerative spine condition that will require surgery.

The surprise announcement immediately scrambled the crowded contest to replace Gov. Sonny Perdue when his second term expires in 2010. Mr. Cagle was considered a front-runner for the Republican nomination with the primary still more than one year away. The 43-year-old Republican from Gainesville said he will seek re-election as lieutenant governor.

He explained that he's had pain in his left shoulder for several years but that it worsened during this year's legislative session and spread to his spine and breastbone. Eventually he began to experience paralysis in his left arm and went to see a doctor.

"I have a very serious issue to my neck, along with my spinal area, that has caused nerve damage that will need to be repaired," Mr. Cagle said at a state Capitol news conference where he was flanked by his wife and three sons.

A neurologist recommended surgery, he added.

Mr. Cagle called the decision to drop his gubernatorial bid "difficult personally for me."

"This is a challenge that I have to face and I will come through it," Mr. Cagle said of his health problems.

Mr. Cagle declined to answer questions.

A spokeswoman refused to provide more details about his condition or the surgical procedure he would undergo, except to say that it would require "a significant recovery period."

Mr. Cagle's withdrawal leaves three Republicans still in the field: Secretary of State Karen Handel, Insurance Commissioner John Oxendine and state Rep. Austin Scott, of Tifton.

Mr. Cagle was elected lieutenant governor in 2006, the first Republican to win the seat in Georgia.