A messy contest is coming to a head behind Donald Trump

AS A HORSE race, the contest to be the Republican Party’s nominee for president is as much of a walkover as they come. Donald Trump has been far ahead all year, and his lead has steadily lengthened. As our , the gap between the former president and his closest challenger, Ron DeSantis, Florida’s governor, from 14 percentage points to a seemingly unassailable 51 points. With Iowa’s big night less than six weeks away, it looks all over bar the caucusing. And if he wins his party’s nomination, Mr Trump would have a good chance of returning to the White House. Analysts at home and abroad are rightly starting to get their minds round what might mean.However, just as in a horse race, the primaries’ front-runner can stumble, or be tripped up by the voters in Iowa and New Hampshire. In Mr Trump’s case, his legal troubles—including four criminal trials and 91 felony charges—could start to look like a threat in the general election. Concerns over candidates’ ability to last the course have understandably centred on the 81-year-old, gaffe-prone President Joe Biden. But the more vigorous-looking Mr Trump is only four years younger and you cannot rule out that a health scare will afflict such a short-fused burger enthusiast. Momentum in politics can change, and a dead-cert can suddenly start losing ground.