By 1884 he was a national figure, and he was nominated as Democratic "clean-government" candidate for President to oppose James G. Blaine. Cleveland, hated by Tammany and favored by political reformers, got the votes of many reform Republicans—the "mugwumps," who voted against their party. The campaign was notably bitter and was marked by the "Rum, Romanism, and Rebellion" speech of a Blaine supporter, which deeply offended Roman Catholics and may have swung the vote to Cleveland in the key state of New York.
Cleveland as President continued his independent and conscientious but conservative course. He did not go far enough in civil service reform to satisfy the zealots, but at the same time by keeping Republican government employees who were not "offensive partisans" he offended the Democratic spoilsmen. Cleveland was continually at odds with the Republican-controlled Senate.
The surplus revenue accumulating in the treasury largely because high Civil War tariffs were still in force fostered much "pork barrel" legislation. Cleveland vetoed such laws and argued for a lower tariff, devoting the whole of his annual message to Congress in 1887 to the question. The tariff was a major issue in the 1888 election. Cleveland received a popular majority but lost the electoral majority to his Republican opponent, Benjamin Harrison. A romantic note in his first administration was his marriage (1886) in the White House to his former ward, Frances Folsom.