Marina Silva, who was running under the banner of the Brazilian Socialist party with Eduardo Campos, was not on the plane that crashed and killed Campos on Wednesday.
Campos and Silva were slowly gaining ground on incumbent Dilma Rousseff though they also had competition from conservative candidate Aecio Neves.
Diario de Pernambuco confirmed that Silva was not on the plane, which crashed on Wednesday morning in Santos.
Globo reported that the small private jet was traveling over a residential area of the city in Sao Paulo state when it crashed.
Campos had a full slate, including a number of interviews and a press conference.
There were seven people on board.
Federal deputy Julie Delgado told the paper: “I’m stunned. We lost Eduardo, a leader of our generation.”
The Air Force confirmed the death. It said the plane took off in Rio de Janeiro and was bound for Guaruja.
The ticket that Campos and Silva were on is now up in the air. She could move up to run for president along with a newcomer in the vice president slot, or she could stay at vice president and someone else could be brought in to run for president. Or the ticket could fall now that Campos is dead.