WASHINGTON - The general who oversees the war in Iraq and Afghanistan slumped at the witness table while testifying at a US Senate hearing Tuesday.Gen. David Petraeus, 57, revived after a few seconds and left the room under his own power. After about 20 minutes he returned to the hearing room, but panel chairman Sen. Carl Levin decided to postpone the hearing."It appears he was maybe a little jet-lagged, dehydrated certainly," said Petraeus' spokesman, Col. Erik Gunhus.Petraeus had finished telling Sen. John McCain that he believed the planned 2011 pullout of US troops in Afghanistan remains on track, and McCain was responding when the room fell silent and aides began crowding around the four-star general.Petraeus, who heads the US Central Command, briefly put his head on the table, then rose, appearing dazed. He stood under his own power and was escorted from the room.Petraeus returned to the room briefly and told the senators he "was feeling a little bit lightheaded there.""It wasn't Sen. McCain's question," the general added.Gunhus said Petraeus had not been ill recently, although he had just returned from a weeklong overseas trip. Gunhus said Petraeus would continue his day as planned.Last year, Petraeus underwent radiation treatment for the early stages of prostate cancer. He later announced the treatment had been successful.In his lengthy appearances before the Senate and House armed services committees in September 2007 to testify on Iraq, Petraeus was reported to have endured great back pain and got through it with the help of Motrin, a pain-relieving drug. .As the most popular and widely known general of his generation, Petraeus is approaching a new juncture in a career that catapulted him to fame when President George W. Bush sent him to Baghdad in early 2007 to carry out a long-shot "surge" strategy that arguably rescued Iraq from collapse.The general has had a high-profile career, and many believe he is the leading candidate to become the next chairman of the Joint Chiefs of Staff.