Bitter Race Exposed Nation’s Social and Economic Fault Lines.

President Dilma Rousseff won a second term on Sunday, defeating the conservative Aécio Neves in an acrimonious race that inflamed social and economic divisions in an emerging giant humbled by falling commodity prices. With 99.7% of the ballots in, Ms. Rousseff had 51.6% of the vote, compared with 48.4% for Mr. Neves. The victory was a testament to the endurance of Ms. Rousseff’s left-wing Workers’ Party, which came to power in 2003 and engineered a come-from-behind win against difficult odds. Ms. Rousseff ran as an incumbent in a country with a stagnant economy and a large population clamoring for change. Barely a year ago, protests over the poor quality of government services made her seem vulnerable. But Brazil’s first female president won four more years by nurturing deep support among Brazil’s poor, who have benefited under a major expansion of the welfare system, and with a late surge in female voters. To do it, the Rousseff campaign painted the two-time governor Mr. Neves as an uncaring snob who would endanger benefits for the poor.

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