In 1812, Van Buren won his party's nomination for a seat in the New York State Senate. Though several Democratic-Republicans, including John Peter Van Ness, joined with the Federalists to oppose his candidacy, Van Buren won election to the state senate in mid-1812. Later in the year, the United States entered the War of 1812 against Great Britain, while Clinton launched an unsuccessful bid to defeat President James Madison in the 1812 presidential election. After the election, Van Buren became suspicious that Clinton was working with the Federalist Party, and he broke from his former political ally.