Which two groups of Congress voted for the U.S.A to join the war?

Established by Article I of the Constitution, the Legislative Branch consists of the House of Representatives and the Senate, which together form the United States Congress.

Explanation:

During the interwar period, the US population was more isolationist than ever--having lost many American lives in a war across the Atlantic. This of course changed when Japan bombed Pearl Harbor, and the US because incredibly active in fighting the Axis powers.