Brazil Presidential Election Second Round margin: Flávio Bolsonaro by under 4% at 40% on Polymarket, on $298K traded in 24 hours

A Polymarket contract covering Brazil’s presidential runoff margin put a Flávio Bolsonaro victory by under 4% at 40%, with $298K traded over 24 hours, according to the supplied headline published Oct 16, 2026, at 3:54 PM ET.

The polydict.app snapshot provides a slightly different volume figure: $293K over 24 hours, with the displayed Bolsonaro margin outcome also at 40%. That listing is timestamped Oct 16, 08:09 PM UTC. The material does not explain the difference between the two volume readings.

Margin pricing versus the overall winner

According to polydict.app, the separate Brazil Presidential Election market priced Flávio Bolsonaro at 76%, with $1.1M in 24-hour trading volume. Both that market and the second-round margin market list an end date of Oct 26, 2026.

Those prices address different questions. The 76% reading concerns Bolsonaro winning the election, while the 40% reading concerns a particular victory-margin outcome. The latter should not be interpreted as his overall probability of winning.

What the listing establishes

The margin contract appeared at number 30 in polydict.app’s displayed list, with seven additional outcomes indicated. Its abbreviated outcome label shows “Flávio Bolsonaro 4%”; the supplied headline identifies the band as under 4%. The excerpt does not include the full outcome definitions or settlement criteria needed to verify that boundary independently.

According to polydict.app, the markets it displays use Polymarket’s order book and settle under Polymarket’s contracts. Shares trade between $0 and $1, with winning shares paying $1 and losing shares paying nothing; resolution depends on each market’s rules and designated source.

What it means for prediction markets

• Winner and margin are distinct exposures: The 40% margin reading is not interchangeable with the 76% Bolsonaro election-winner reading.
• Volume figures need their timestamps: The headline reports $298K, while the supplied polydict.app snapshot reports $293K. Neither establishes a trading trend on its own.
• The margin boundary matters: The headline specifies under 4%, but the abbreviated listing does not independently establish the precise settlement threshold.
• A snapshot is not evidence of a move: The supplied material contains no earlier price comparison showing whether the 40% reading rose or fell.