Ricky Stenhouse Jr. will lead the 40-car field to the green flag, as he qualified on the pole.
Prior to calling for the race to resume on Monday, NASCAR ordered drivers to their cars before rain resumed.
He'll be the second sitting president to attend the event - the first being George W. Bush in 2004.
Trump, who was endorsed in 2016 by former NASCAR CEO Brian France Jr., has hosted series champions Joey Logano and Martin Truex Jr.at The White House and gave NASCAR team owner Roger Penske the Presidential Medal of Freedom previous year.
The first delay lasted 50 minutes and came moments after the presidential motorcade completed a ceremonial parade lap around the 2 1/2-mile track. Which is notable considering next week's Cup race will run at Las Vegas Motor Speedway. Drivers were then given a caution when more rain started falling, which quickly turned into a red flag.
Crew members wave to President Donald Trump prior to the start of the Daytona 500 at Daytona Int'l Speedway.
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Given the honour of commanding drivers to start their engines, Mr Trump made a grand entrance before the start of the race, becoming the second president to attend the race after George W. Bush, also in his reelection year.
Inside, President Trump met NASCAR Cup Series drivers Clint Bowyer, Bubba Wallace, Ricky Stenhouse Jr., Kurt Busch, Aric Almirola, Austin Dillon, Chase Elliott, former Cup Series champion and two-time Daytona 500 victor Bill Elliott and young gun Hallie Deegan.
Democrat Bill Clinton attended a NASCAR race as a presidential candidate in September 1992, but many fans at the Southern 500 in Darlington, S.C., booed and heckled him over the question of his lack of Vietnam-era military service that stalked his campaign.
But the start of the race was delayed when light rain hit for almost an hour. It was an honor to open the Daytona 500.
NASCAR stopped disclosing the prize money teams earn in races in 2016, but Logano earned $1.58 million for winning the 2015 Daytona 500.
It isn't every day that you'll see a Presidential limo lapping the Daytona 500, but today might be the one.