Answer:
opposition to the war in Iraq
Step-by-step explanation:
Barrack Obama won the decisive victory over McCain in the United States 56th Presidential election race. The main issue that helped to determine the outcome of the Presidential race of 2008.
It was 56th quadrennial presidential election, which was held on the 4th November, Tuesday, 2008. In this election, Democratic senator from Illinois, Barrack Obama won the election over Republican John McCain and sworn as the President of US.
Barrack Obama is the first African American who is ever elected to this post.