Rep. Mike Pence (R-Ind.) reached Rep. Steve Buyer (R-Ind.) on his cell phone Thursday night, aware that his colleague was shipping out to the Persian Gulf within days.

"Is this Colonel Buyer?" Pence asked.

"Yes, how can I help you, sir?" replied Buyer, a six-term House member and lieutenant colonel in the Army Reserves.

"Are you really being called up?" Pence asked.

"As soon as you heard me call you 'sir,' you should know I'm activated military," Buyer said.

This week, Buyer (pronounced BOO-yer) informed House Speaker J. Dennis Hastert (R-Ill.) and a few other colleagues that he was heading to the Persian Gulf, where he served more than a decade ago during the first Gulf War. He will serve as an operational law judge advocate in a POW camp with a forward-deployed unit.

Buyer is one of nearly 200,000 reservists nationwide who are shelving their regular jobs to support the armed assault against Iraq. The number of military veterans in Congress has dwindled steadily over the past decade, but there are several who see their service in the armed forces as helping to define their career and character.

"I cannot separate myself from my war experience," Buyer once said. "I don't remember that person I was before I left."

Buyer is not the first member of Congress to deploy overseas during wartime, nor is he the House's only active reservist. For example, Rep. Mark S. Kirk (R-Ill.), who flew combat missions over Kosovo and Iraq, has been on active duty at the Pentagon since January. He said he hopes to ship out with a Navy carrier during the House's spring break next month.

"In today's military, many of the key functions on the first day of battle will have been performed by reservists," said Kirk, a watch officer who reviews classified information and news reports to brief the Joint Chiefs of Staff and Secretary of State Colin L. Powell on international events.

Members of Congress are exempt from military service if they choose. But Buyer was ready to deploy, his spokeswoman, Laura Zuckerman, said. Buyer declined to be interviewed.

"A need was identified, of which Congressman Buyer has the unique skill and experience to meet the requirements within the theater of operations," Zuckerman said.

Buyer's friends said the House member is uneasy about leaving his family but eager to participate in a preemptive strike that he advocated as a lawmaker. "He is a dedicated member of Congress, but if you cut him, he bleeds military green," Pence said.

Thursday night -- a day after Buyer left Washington to spend time with his family before shipping out -- colleagues gave him a standing ovation on the House floor.