Trump and Biden Get Ready for the Very Long Haul

With Donald J. Trump rapidly closing in on the Republican presidential nomination, the 2024 general election campaign is set to be one of the longest in modern history, pushing President Biden and Mr. Trump into unfamiliar territory as they struggle to engage an electorate that seems numbed by the prospect of a 2020 rematch.

For all their experience in presidential politics, Mr. Biden and Mr. Trump face extraordinarily complicated challenges as they and their aides grapple with how to run a presidential campaign that will last almost nine months, significantly longer than most general election contests.

This is a race that has been run before, a rematch between two older and by now well-known candidates: Mr. Trump is 77, and Mr. Biden is 81. Mr. Trump has essentially been a candidate for re-election since his defeat four years ago and may spend much of the spring fighting felony charges in court. Both men are unpopular with large numbers of voters.

“What can they possibly say about their opponent that voters don’t already know?” said Mark McKinnon, who was the chief media adviser to George W. Bush for his 2000 and 2004 campaigns.

The time between the end of the primaries and the party conventions usually brings a lull in the campaign, when presumptive nominees test attacks on opponents, shore up their shortcomings and build the policy, political and financing foundation for the fall campaign. That period usually begins in late spring, but if Mr. Trump maintains his commanding lead over Nikki Haley, the former ambassador to the United Nations, it could start before winter is through.

As a result, the Biden and Trump campaigns face a series of unusual strategic decisions in the weeks ahead: How much of the next nine months do