Final answer:
The election of 1912 was unique because it was a four-way race between Taft, Roosevelt, Wilson, and Debs. It was also the first time a third-party candidate received more votes than an incumbent president. The election led to a major political realignment.
Step-by-step explanation:
The election of 1912 was unique for several reasons. It was a four-way race between incumbent President William Howard Taft, former President Theodore Roosevelt running as a third-party candidate, Woodrow Wilson representing the Democratic Party, and Eugene Debs as the Socialist Party candidate. This was the first time that a third-party candidate received more popular votes than an incumbent president. Additionally, the election resulted in a major political realignment, with Wilson and the Democrats winning the next five consecutive presidential elections.