2020 U.S. presidential primary race moves to U.S. states of Arizona, Florida, Illinois

The primary race of the 2020 U.S. presidential election moved to the U.S. states of Arizona, Florida, and Illinois on Tuesday, amid a greater concern over the COVID-19 pandemic.

Former U.S. Vice President Joe Biden is ahead of Vermont's Senator Bernie Sanders in polling in all three states.

The two are locked in a one-on-one battle for the Democratic Party's nomination to challenge sitting president Donald Trump, a Republican.

Ohio was meant to vote on Tuesday but the state's health director ordered the closure of all polls based on the COVID-19 public health emergency.

Election officials in Arizona, Florida, and Illinois have said they would take additional health precautions to ensure a safe voting environment.

Besides Ohio, Georgia, Kentucky, and Louisiana have postponed their primaries due to the COVID-19 situation.