By james art Top line
The presidential election prediction markets turned on Vice President Kamala Harris on Friday, giving Harris the strongest and former President Donald Trump the weakest odds of winning next week’s election in more than a week at betting sites, although the odds they still prefer Trump.
The betting odds shifted in favor of Harris on Friday, but are still in Trump’s favor.
Key facts
Harris’ winning odds stood at 42.4% on Friday afternoon, the highest since last Thursday, with Trump back at an eight-day low of 57.2%, according to Election Betting Odds, which tracks the movements of the odds on five platforms that allow users to bet on the outcome of the election.
The split on crypto-based Polymarket, which is not legal in the US but is perhaps the best-known of the sites, shrank to 60.3% odds for Trump compared to 39.6% for Harris, down from a three-month low of 33 .1% certain Wednesdays.
Polymarket competitors Kalshi and PredictIt, both of which operate legally in the States but have relatively low betting limits per user, show an even steeper tilt towards Harris.
Kalshi prices Harris with a 45% chance of winning, compared to the site’s Wednesday low of 35%, and PredictIt gives Harris about 49% implied odds, compared to this week’s low of 41%.
A big number
48%. Those are the odds based on FiveThirtyEight polls that have Harris winning, compared to 52% for Trump. Other poll-based models show a narrower split than the betting markets, with the Economist favoring Trump by a 51% to 48% margin.
How election betting works
Platforms accept bets for a particular candidate to win, with payouts depending on the market odds on the day of the bet. So if a bettor bet $100 on a 50% odds candidate, they would receive roughly $100 in profit if that person wins, or lose $100 if their pick loses (not counting fees taken by the betting site). Odds move for presidential election markets similar to other betting markets such as sports betting, meaning a key injury update that would change the betting odds for a given game should have a similar effect to a swing poll, more favorable from previous surveys for a particular candidate.
Key background
Election betting has become a popular topic of discussion this election cycle, with some pundits touting the market as a useful indicator of the likelihood of the actual outcome of the election, given that users are financially incentivized to get their predictions right. Others questioned the impact individual traders could have on the odd moves, and some like Polymarket pollster and adviser Nate Silver noted that the odds may be skewed toward Trump because the demographic placement of those bets could prove politically correct . More established brokerages such as Robinhood and Interactive Brokers have launched their own election betting platforms in recent weeks. Polls point to an extremely close race between Harris and Trump.
Further reading
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