Washington (AFP) - Elections in the United States are regularly marred by technical hitches, such as the fiasco in Iowa where the Democratic primary results were delayed due to "inconsistencies" in reporting.

Complex electoral system

The technical problems that surface during US polls are in part explained by the complexity of its electoral system.

Organizing elections is a major challenge as Americans are often required to vote on the same day in national and local elections, and also to select city officials, judges, police chiefs and even in decide in referendums.

Added to this, because elections are run locally, the voting systems vary from place to place. Congress in 2018 ruled against setting nationwide standards and audits.

The rules for organizing primaries and caucuses -- the process by which a party nominates its candidate to run in an election -- also vary according to place.

Florida debacle

In the 2000 presidential election, badly punched cards caused by defunct machines -- such as the "hanging chads" -- provoked massive confusion in Florida. 

In some cases the punching machines had made only partial holes, leaving it up to the counters to determine voters' intentions. 

On polling night, only a few hundred votes separated Republican candidate George W. Bush and his Democratic rival Al Gore in the state, on which the entire election was to be decided.

A five-week legal battle ensued and the votes were recounted by hand.

Tens of thousands of ballots were canceled for having punch marks next to the names of several different candidates.

The Supreme Court eventually put an end to the chaos and declared Bush the winner.

Tech bugs

To avoid a repeat of the 2000 Florida fiasco, many authorities opted for electronic voting machines to be used in subsequent elections.

But blunders still occur regularly, albeit not on the same scale and import as Florida.

In parliamentary elections in 2006, technical hiccups marred voting with reports of broken machines in Indiana, Ohio, Pennsylvania, Colorado and Utah, leading to some polling stations staying open for longer hours.

Election Protection, a nonpartisan US election watchdog, said in a report on its website that six percent of the calls it received in the 2018 midterm elections were about problems with voting machines, from defective devices to inaccessibility for the disabled.

Hacking fears

Voting machines also raise the specter of cybersecurity. 

Faults can allow hackers to enter voting machines or electoral systems and as some devices do not produce copies of voters' ballots there is no way to verify whether or not a ballot has been rigged.

In 2016 US intelligence said Russian agents had tried to access the electronic electoral lists of some 20 states and accessed at least one of them, though without apparently modifying the data.

Washington announced in November 2019 that it had strengthened its election security across the country.