Starting even before Election Day, Mr. Trump and his Republican allies have filed nearly five dozen challenges to the handling, casting and counting of votes in courts in at least eight different states.
They generally lost those cases, often drawing blistering rebukes from the judges who heard them. Along the way Mr. Trump has not come close to overturning the election results in a single state, let alone the minimum of three he would need to seize victory from Mr. Biden.
The first batch of actions preceded the election and sought to end or pare back voting measures that states across the country had put in place to deal with the coronavirus crisis. In Texas, for instance, Republicans pursued a failed effort in federal court to stop drive-through voting in Harris County, home to Houston. A similar move was made in Pennsylvania to stop the state from accepting mail-in ballots received after Election Day.
Mr. Trump and his allies switched tactics after the election, filing a barrage of suits in Nevada, Arizona, Pennsylvania, Michigan, Wisconsin, Minnesota and Georgia claiming that all manner of fraud had compromised the vote results.
They made accusations that truckloads of illegal ballots were brought in under cover of darkness to a convention center in Detroit; that poll workers in Atlanta were given suitcases full of fake ballots for Mr. Biden; that Iran and China, working with local elections officials, had hacked into and manipulated algorithms in voting machines.
While some of these claims were supported by sworn statements from witnesses, judge after judge in case after case ruled that the evidence was not persuasive, credible or anywhere near enough to give Mr. Trump the extraordinary relief he requested: a judicial order overturning the results of an election.
What is left is a judicial mopping-up exercise. Several suits that the president and his supporters have lost in lower courts are now on appeal, in both the state and federal systems, but the appellate process is quickly running up against a crucial deadline on Monday when the Electoral College meets and Mr. Biden is expected to prevail in the voting, all but sealing the results of the election.
Alan Feuer and Maggie Haberman contributed reporting from New York.