An al-Qaeda supporter has called for a pre-election terror attack in the US to help Republican candidate John McCain win the presidency.

Al-Qaeda can better achieve its goal of weakening the US military and economy if Republican candidate Senator John McCain is elected as president, a message posted on the al-Hesbah Website said on Monday.

"This requires presence of an impetuous American leader such as McCain, who pledged to continue the war till the last American soldier,'' the message said, according to an AP report.