Colombians return to the polls Sunday for a presidential runoff between a far-right firebrand who calls himself “the Tiger” and a left-wing senator from the ruling party, in a contest that reflects sharply different visions for the country and could redefine Bogotá’s relationship with the United States.

Colombia’s runoff is a vote on security, Petro’s legacy and the country’s place in a changing Latin America

On Sunday, Colombians will choose between human rights activist Ivan Cepeda, who would continue a more liberal agenda, or entrepreneur Abelardo de la Espriella, who promises a…