The Payne-Aldrich Law served to widen a split which was already making itself felt in the Republican party. The more progressive leaders of the party felt that it was not living up to its best traditions as a friend of the masses. Gradually the breach widened, until those who desired to work reform within the party came to be known as insurgents. By the spring of 1912 the feeling had become bitter. President Taft was supported for reelection by the conservatives of the party, while the more liberal elements favored ex-President Roosevelt. Both men were finally nominated, one by the Republicans, the other by the Progressives. Division meant defeat. The Democrats elected Woodrow Wilson, their candidate for president, and likewise a Democratic Congress.

Once again in control of the government, the Democrats began to lay plans to revise the tariff. Congress spent months in examining witnesses, and in discussing the advantages and disadvantages of each rate. Finally in 1914 the Underwood-Simmons Tariff Law was sent to the president for his signature. This act, as might be expected, lowered many rates, and enlarged the free list. To offset any decrease in revenue that might arise from these changes, an income tax, conformable to a recently ratified amendment to the Constitution, was imposed.