His administration was filled with conflict between the conservative wing of the Republican Party, with which Taft often sympathized, and the progressive wing, toward which Roosevelt moved more and more during Taft's presidency. Controversies over conservation and over antitrust cases filed by the Taft administration served to further separate the two men. Roosevelt challenged Taft at the 1912 Republican National Convention, but Taft was able to use his control of the party machinery to narrowly win his party's nomination. After the convention, Roosevelt left the party, formed the Progressive Party, and ran against Taft and Wilson the 1912 election. This split among Republicans doomed Taft's chances for re-election, giving Democrats control of the White House for the first time in sixteen years as well as Congress. Historians generally consider Taft to have been an average president.