Washington - President George W Bush and his wife Laura may have cast their election ballots early, but apparently there was some skepticism as to just which candidate they voted for.

"Today the President and Mrs Bush cast their ballots for the 2008 election during the early voting process. The ballots will be mailed back to Texas today," White House press secretary Dana Perino wrote in an emailed statement Friday.

Notice she failed to mention for whom? The media apparently did. About 20 minutes later came a second email.

"I find this hard to believe ... But so many reporters have asked just who the president voted for, I guess I have to make it clear - for months the president has said he supports John McCain for president and of course he voted for him," Perino wrote.

But the confusion was a sign of the times. Bush, whose approval ratings have fallen below 30 per cent amid an unpopular war in Iraq and a financial crisis that may have tipped the US into recession, has been mostly absent from the campaign trail this year.

The outgoing president endorsed fellow-Republican McCain in March but the two have appeared only once in public together since - in May on an airport tarmac ahead of a fundraiser. Bush's limited role has largely been behind the scenes, at a few select private functions.

The president's absentee vote itself marked a clear departure from past years, when Bush cast his ballot on election day in his home town of Crawford, Texas. Perino said Bush would spend election night on November 4 at the White House.

Democratic presidential nominee Barack Obama has regularly sought to link McCain to the Bush administration - pointing especially to his economic plans and stance on Iraq - charging the country can't afford "four more years like the last eight."

McCain, who prides himself on a maverick reputation and willingness to take on his own party, has fought hard to distance himself from the current president during the 2008 election campaign.

"Senator Obama, I'm not President Bush," McCain said in one of the more memorable moments of the candidates' final debate earlier this month. "If you wanted to run against President Bush, you should have run four years ago."

This week McCain used some of his toughest rhetoric yet, blasting Bush and the Republican party in an interview with the Washington Times.

"We just let things get completely out of hand" over the past eight years, he told the paper, citing higher government spending and the conduct of the post-war phase in Iraq.

Comments like those prompted reporters to ask Perino on Thursday whether Bush takes the campaign rhetoric personally.

"No, he doesn't," she said. "The president stands by his policies. He also stands by John McCain." (dpa)