SAO PAULO, Sept 21 (Reuters) - Brazilian President Luiz Inacio Lula da Silva and Senator Flavio Bolsonaro remain statistically tied in a simulated runoff ahead of next month's election, a BTG Pactual/Nexus poll showed on Monday, with the leftist incumbent holding a narrow lead within the survey's margin of error.
• If there was a runoff, Lula would receive 46% of voter support, compared with 45% for the eldest son of former President Jair Bolsonaro, the poll said.
• A September 14 survey had Lula leading Bolsonaro by 47% to 46%.
• In a first-round scenario, Lula would lead with 40% of the votes, followed by Bolsonaro (37%), Augusto Cury (6%), Ronaldo Caiado (5%) and Renan Santos (3%).
• The previous first-round survey had Lula at 42%, Bolsonaro at 37% and Cury at 6%.
• If no candidate wins more than 50% of valid votes in the October 4 first round, the two frontrunners advance to a runoff on October 25.
• Nexus surveyed 2,006 people from September 18 to 20. The poll has a margin of error of 2 percentage points.
(Reporting by Rodrigo Viga Gaier in Rio de Janeiro, Michael Susin in Barcelona and Gabriel Araujo in Sao Paulo; Editing by Isabel Teles)
