Ugandans began voting on Thursday in a hotly contested election that will decide whether President Yoweri Museveni wins a sixth term in office and continues his 35-year rule of the country or is unseated by one of 10 rivals, including a leading opposition candidate, Bobi Wine, a rapper-turned-lawmaker. The vote, which has been unexpectedly competitive despite fierce government attempts to stifle the opposition, has drawn global attention as a test of how democracy might take hold in a country more accustomed to autocratic rule. The election is the fourth in the East African nation since multiparty politics was restored in 2005, two decades after Mr. Museveni first came to power and clamped down on competing parties. The ballot also comes several months after the government introduced strict rules to curb the coronavirus pandemic — measures that have kept confirmed caseloads under 38,000, but which human rights groups said were used to crack down on critics and restrict political gatherings.