Polls closed in Bolivia on Sunday after a calm election as President Evo Morales sought an unprecedented fourth term in what was regarded as the tightest race of his political career. The 59-year-old leftist who has been in office for nearly 14 years was favored to win the first round vote. But polls suggested South America's longest-serving leader would likely be forced into a December runoff in which he could be vulnerable to a united opposition. Voting, which was mandatory, was mostly calm, though police said they arrested more than 100 people for violating the country's rigid election-day rules against drinking, large gatherings or casual driving. Morales voted early and said he remained confident of the results. Polls closed at 4 p.m. and early quick counts were expected Sunday night.