The 1864 United States presidential election was the 20th quadrennial presidential election. It was held on Tuesday, November 8, 1864. Near the end of the American Civil War, incumbent President Abraham Lincoln of the National Union Party easily defeated the Democratic nominee, former General George B. McClellan, by a wide margin of 212–21 in the electoral college, with 55% of the popular vote. For the election, the Republican Party and some Democrats created the National Union Party, especially to attract War Democrats.

Abraham Lincoln was an American lawyer, politician, and statesman, who served as the 16th president of the United States, from 1861 until his assassination in 1865. Lincoln led the United States through the American Civil War, defending the nation as a constitutional union, defeating the insurgent Confederacy, playing a major role in the abolition of slavery, expanding the power of the federal government, and modernizing the U.S. economy.