The Election of 1856 marked the end of the Second Party System, which had been dominated by the Democrats and the Whigs, and the beginning of the Third Party System, which was characterized by the emergence of the Republican Party. The election highlighted the growing tensions over slavery in the United States, and the Republicans, who were strongly opposed to the expansion of slavery, made significant gains in the North. Although the Democrat James Buchanan won the election, the Republicans demonstrated their growing political power and influence, paving the way for their eventual dominance of American politics in the decades that followed.