WASHINGTON, Feb 4: The White House swung into campaign mode on Tuesday to defend President George W. Bush's record in the Texas Air National Guard far from the battlefields of Vietnam after Democrats accused him of going "AWOL (absent without leave)."

White House spokesman Scott McClellan denied Democratic charges that Bush shirked his military duties in the early 1970s unlike Democratic presidential front-runner John Kerry, a decorated Vietnam veteran.

McClellan called the accusations "shameful" and the "worst of election-year politics." Bush "fulfilled his duties" in the National Guard and was honorably discharged. "The president was proud of his service," McClellan added.

The counter-attack came as voters voted in seven states on the biggest day yet of a Democratic presidential race so far dominated by Kerry.

Analysts said the unusually blunt response underscored White House concerns that military service could become a campaign issue.

Bush stayed out of combat in Vietnam while serving as a pilot in the Air National Guard.

Democrats have long challenged Bush's record of attendance in the guard in 1972 when he transferred temporarily to an Alabama unit to work on a political campaign.

According to a copy of the National Guard document granting him an "honorable" discharge on Oct. 1, 1973, Bush completed five years and four months of service - less than the obligatory six years - before entering Harvard Business School.

On Sunday, Democratic National Committee Chairman Terry McAuliffe thrust the issue to center stage, telling ABC's "This Week" television program that he welcomed a debate on military service if Kerry won the party's presidential nomination.

"I look forward to that debate when John Kerry, a war hero with a chest full of medals, is standing next to George Bush, a man who was AWOL in the Alabama National Guard," McAuliffe said. "George Bush never served in our military in our country. He didn't show up when he should have showed up."-Reuters