Keep an eye out for the Trump Train in the Hawkeye State. The latest conference of the International Atlantic Economic Society was held very recently in Washington DC to coincide with the run-up to the US Presidential and Congressional elections. The conference included a special session on election analysis and forecasting at which I was asked to speak on the theme of forecasting an election. Despite a detailed explanation of the theory underpinning the science of state-of-the-art political forecasting, of most immediate interest to the conference delegates was the state of play in the 2016 race, and most critically the likelihood that Hillary Clinton would defeat Donald Trump.

Based on the latest data available at the time of the conference, I explained to the audience that Hillary Clinton was a very strong favourite on almost all metrics to win the White House, but warned them that even very strong favourites lose sometimes. On seven parallel worlds, Secretary Clinton would win on six of them and Mr. Trump on one. But it’s quite possible, I pointed out, that we are living on Planet Seven. That remains the case.

If we are living on Planet Seven, the biggest reason for the Trump victory, I said, lay just a ten minute walk away, a walk I had taken a couple of days earlier. It was to attend a live session of the US Supreme Court, in which I witnessed conservative Chief Justice John Roberts and liberal Justice Elena Kagan questioning Counsel in the case of Manrique v. United States, following earlier oral arguments in Samsung Electronics v. Apple Inc., a case arising out of Apple’s allegation that Samsung’s smartphones infringed its patents for the design of its iPhones. For in the selection of the next Justice to replace arch-conservative Antonin Scalia on the bench, and possibly three more Justices over the next four years, lies the political balance of the Court for at least the next couple of generations. The whole future of abortion rights, gender equality, gun control, health care, campaign financing, will turn on the make-up of this Court. It is the main reason given for sticking with the Trump train by those who have given up on Donald Trump in almost every other way. Securing the Supreme Court, to many Republicans, is pretty much worth anything.

If Trump does win, that in my view will be the reason. But even if he doesn’t win the national race, there is a State that the Supreme Court card might well tip in his favour. It is known as the Hawkeye State, its demographics favour Trump, and the winner of the popular vote gains its six electoral votes. Its caucuses also traditionally mark the beginning of the race to the White House. It is the State of Iowa.

According to the RealClearPolitics average of polls, Trump is leading, at the time of writing, by 3.7 per cent in Iowa. HuffPost Pollster, which uses a somewhat different selection of polls, puts Trump up about one percent, with the poll using the biggest sample (the Washington Post/Survey Monkey poll) having him up by 5. The FiveThirtyEight ‘polls-plus’ forecast, which also includes data on the economy and historical data, also currently tips it slightly to Trump, as does the PredictIt prediction market. What is particularly interesting about this polling and prediction market data is best seen through the lens of a paper I co-authored with Dr. James Reade, titled ‘Forecasting Elections’, which was recently published in the Journal of Forecasting. In that paper, drawing upon a huge data set of election betting, polling, modelling and expert judgment to determine the most accurate election forecasting methodology, we showed that prediction markets offer the most accurate way of pinpointing the likelihood of an election winner, and tend to become more accurate as an election approaches, while polls actually tended to be at their most accurate a few weeks out from the election. On this basis, the current polling and the customised prediction market, identified above, point in the same direction, to an election in the Hawkeye State which is simply too close to call, but is leaning slightly to the Republican.

At any price long of evens, a bet on Donald Trump would seem, therefore, to offer a touch of value. For this reason, the 5/4 about Trump to win Iowa, currently available with BetVictor, might well be worth considering.

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Trump to win Iowa - 1pt @ 5/4