Yes it's likely, though it wouldn't have been easy for Roosevelt to accomplish as it was with Germany declaring war on the U.S. Without the casus belli of Germany declaring war, finding an adequate reason to push congress and the American people would have taken more time.

As early as January 1941, President Roosevelt, Secretary Stimson, General George Marshall, and Admiral Harold Stark had begun meeting and planning future operations with senior British officers who had secretly arrived in the U.S. with the new British Ambassador, Lord Halifax. While the meetings between the two groups were conduced under the utmost secrecy as to not jeopardize the Lend-Lease Act being debated in Congress nor American Neutrality (which was tenuous at best as far as the war in Europe was concerned, the U.S. was more a less already fighting an undeclared war against the Kriegsmarine and U-Boat attacks in the Atlantic. Also after the passage of Lend-Lease, directly supplying two belligerents with arms and supplies), the two groups came to an important understanding about what the future held in store for American-British Military relations in regards to the possibility of the U.S. entering a two-front war.

The most important thing agreed upon by both parties was that even though Japan was the more seemingly the most clear threat facing the U.S., Europe would be the first priority in any near future conflict, since it was agreed that if England was knocked out of the war by Germany, their ability to assist with operations against the Japanese and Germans (even if they continued the fight from Canada or South Africa) would be directly hindered, and the balance of power would greatly shift against the U.S. and U.K.

As General Marshall put it bluntly "Collapse in the Atlantic would be fatal; Collapse in the Far East would be serious but not fatal." It's obvious that with this in mind, Roosevelt, the War Department and his top military staff would have still seen Europe as the dominant threat in comparison to Japan (even with the attack at Pearl Harbor, the U.S. still had the ability to at least hold the line until the fleet could be rebuilt and redeployed against the Japanese).

If Germany hadn't declared war on the U.S. , it could be argued that the U.S. may have not declared war on Germany as soon as it did, if at all, especially considering the high feelings of isolationism and "America First" running through the nation prior to Pearl Harbor. Though I think that's a difficult position to argue from (The U.S. not declaring war at all) , considering that the amount of U.S. aid being sent to the U.K. and the Soviet Union as well as the constant attacks upon American vessels by U-Boats would have made officially staying out of the European conflict difficult for much longer even without Germany's deceleration. I think if pressed, Roosevelt may have used the Tripartite Pact as evidence that Japan was not the only threat the U.S. faced in a war against aggressive expansionism and in order to adequately defend U.S. interests, direct action would be needed against all parties of the Tripartite Pact to ensure the protection of American interests.

After Pearl Harbor, Roosevelt was obviously still caught in a difficult position for four days until Hitler and Mussolini both declared war on the U.S. Even with the Axis deceleration of war, Roosevelt was facing intense pressure to focus the majority of American efforts in the Pacific theater rather than Europe due to Pearl Harbor. Without that deceleration of war, it would have been very very difficult, though not necessarily impossible for Roosevelt to keep to his original policy of prioritizing the defeat of the Germans first and foremost. It eventually came down to the Navy agreeing to deploy a large share of it's assets (both in terms of ships and the Marines, which fall under the Navy's purview) to the Pacific while the Army would focus primarily on Europe while still deploying some of it's assets to the Pacific.

Source: Freedom From Fear: The American People in Depression and War, 1929-1945 by David Kennedy pages 485-525