Wagering on papal elections is a tradition roughly as old as the Sistine Chapel, with scholars having found records of betting odds for the papacy as far back as 1503. The conclave that begins Wednesday involves a new twist: It’s the first time that major online prediction markets have turned their focus on the Vatican’s ancient selection process.

And wagers are flowing in. Cardinal Pietro Parolin of Italy has emerged as the odds-on favorite to succeed Pope Francis, according to the prediction markets Polymarket and Kalshi. Even a report last week that the 70-year-old cardinal had medical issues, which the Vatican denied, did little to dent that lead. The other top contenders as of Wednesday morning, according to the betting sites, are Cardinal Luis Antonio Tagle of the Philippines and Cardinal Matteo Zuppi of Italy.