Many unknowns remain about what lies ahead in terms of the effects COVID-19 has on our lives. One thing is true though it is not likely. President Trump does not have the power to delay the 2020 election and neither does Congress because of certain factors at play.

According to Fox News:

Under our Constitution, the executive branch has no authority whatsoever to delay, reschedule or otherwise change the federal election in November, much less any of the remaining state primaries. On the other hand, Congress and the states do have that authority.

Congress has no authority over state elections or party primaries other than the requirements under federal statutes like the Voting Rights Act and various constitutional amendments that prohibit states from discriminating or limiting access to the voting process. But when it comes to setting the dates for political party primaries or general elections for state officials, including presidential primaries, or how you are able to vote (in-person or by mail), the federal government has no power to dictate the time, place or manner of those state elections.

State governments can certainly change the dates of their presidential primaries or whatever other state primaries they are holding.  In some states such as Arizona, Florida, Illinois, Indiana, Michigan, Tennessee, Texas and West Virginia, governors are provided with emergency authority to take such actions without the approval of their state legislatures.

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But the federal government cannot change the date of such state primaries. Given that all 50 states and the District of Columbia allow voters to vote with absentee ballots, which can be easily obtained, completed and mailed without anyone ever leaving their house, there seems little reason to do so. The cancellation and delay in the New York primary because of the 9/11 attacks on Election Day itself was an extraordinary event necessitated by unique and tragic circumstances. That is not the current situation.

The only way this could happen is if both chambers passed legislation to change the prescribed dates for the elections of Congress and the Senate and President Trump signed it into law. This is unlikely to happen since neither party controls all three.