The Iowa State Fair may be fun but the key for most 2020 candidates is simply avoiding a mistake

The Iowa State Fair is a rite of passage for all presidential nominees – taking a tour around the site in Des Moines and indulging in the range of deep-fried snacks on offer and making sure to pose next to the 600lb butter cow.

It is one of the first occasions you know all candidates will likely turn up at some point over 11 days from 8 to 18 August (although Beto O’Rourke cancelled a trip on Thursday to stay in El Paso as the city recovers from a mass shooting). The reason? A mix of tradition and the fact that you don’t want to slight possible voters in the first state to decide their choice for nominee.

In 2020 the Iowa caucuses will take place on 3 February and with Donald Trump a lock-in for the Republican nomination, the caucuses will be particularly important for a crowded Democrat field. A first-place finish in the vote, or even a close second or third will give a candidate momentum going into the next few races. It will also mean an increase in donations and a boost in media airtime.