THE APP at the centre of the chaos around the US Democrats’ Iowa caucus is owned by a billionaire backer of nominee Pete Buttigieg, it emerged today, raising concerns that the party’s elite are trying to rig the vote.

Local party officials blamed the prolonged delay in the results of the poll being announced on a new electronic voting system being used for the first time.

According to a report on the Grayzone website, the app developer — Shadow Inc — is “staffed by Hillary Clinton and Barack Obama campaign veterans and created by a Democratic dark-money non-profit [company] backed by hedge-fund billionaires including [Buttigieg campaign donor] Seth Klarman.”

The firm was created by a non-profit organisation called Acronym, which also gave birth to a $7.7 million (£5.9m) “Super PAC [political action committee] known as Pacronym,” whose largest donor is Mr Klarman, according to the report.

Journalist Lee Fang published details on Twitter showing that Shadow Inc had been paid for “software rights” by the Buttigieg campaign.

Confusion over the vote led left-wing hopeful Bernie Sanders to delay a speech, with Mr Buttigieg using the moment to declare himself victor on Monday.

While Iowa awards only 41 of the 1,991 delegates required to secure the Democratic presidential nomination, its status as the first state to vote gives the victor momentum. Since 2000, every candidate that has won the state vote has gone on to be the Democrats’ candidate in the race for the White House.

With 71 per cent of the precincts counted when Star went to print, Mr Buttigieg was reported to be on 26.8 per cent, ahead of Mr Sanders on 25.2 per cent, and each with the same number of electoral-college delegates.