[208] He continued to closely watch political developments, including the battle between the Whig alliance of the Great Triumvirate and President John Tyler, who took office after Harrison's death in April 1841.[209] Though undecided on another presidential run, Van Buren made several moves calculated to maintain his support, including a trip to the Southern United States and the Western United States during which he met with Jackson, former Speaker of the House James K. Polk, and others.[210] President Tyler, James Buchanan, Levi Woodbury, and others loomed as potential challengers for the 1844 Democratic nomination, but it was Calhoun who posed the most formidable obstacle.[211]
Van Buren remained silent on major public issues like the debate over the Tariff of 1842, hoping to arrange for the appearance of a draft movement for his presidential candidacy.[212] Tyler made the annexation of Texas his chief foreign policy goal, and many Democrats, particularly in the South, were anxious to quickly complete it.[213] After an explosion on the USS Princeton killed Secretary of State Abel P. Upshur in February 1844, Tyler brought Calhoun into his cabinet to direct foreign affairs.