On Tuesday, March 17, Arizona, Florida and Illinois each hold Democratic and Republican primaries. Ohio was also scheduled to hold its primary, but Gov. Mike DeWine tweeted late Monday night that polls would be closed as a matter of a public health emergency as the state seeks to further press its legal case in court to extend primary voting to June 2 due to the coronavirus crisis.
All four states together represent the third-largest delegate haul of the primary calendar, with 577 Democratic and 328 Republican delegates at stake.
March 17 significance
A lot hangs in the balance on March 17, as nearly 15% of all primary delegates will be awarded in these contests.
Florida -- known as a key battleground state -- has the most delegates up for grabs: 219 for Democrats and 122 for the Republicans.
For Democrats, there are 155 delegates up for grabs in Illinois, 136 in Ohio and 67 in Arizona. The outcomes could have a significant effect on what is now essentially a two-person race.
On the Republican side, President Donald Trump is likely to hit the threshold for the required number of delegates, clinching his party's nomination.