President Biden and former President Donald J. Trump won overwhelming victories in state primaries on Tuesday, while a small but significant protest vote in both parties continued to assert itself against each candidate.

Mr. Biden and Mr. Trump, who have already clinched their nominations, scored yawning leads in primaries in Connecticut, New York, Rhode Island and Wisconsin, with the races called shortly after polls closed in each state.

Mr. Trump held at least 75 percent of the vote in every state as of 11 p.m. But Nikki Haley, who dropped out of the race early last month, still took at least 10 percent of the vote in all four states, a sign of lingering discontent in the Republican Party with Mr. Trump’s candidacy. Mr. Trump was weakest in Connecticut, where he notched under 78 percent of the vote, while Ms. Haley took about 14 percent.

Mr. Biden held at least 80 percent of the vote in every primary as of 11 p.m. Activists have urged primary protest votes as a way to register disapproval over Mr. Biden’s handling of the war in Gaza, and the “uncommitted” ballot option took between 8 and 15 percent of the vote in the states where that was an option. In Rhode Island, 14.9 percent of voters chose the “uncommitted” ballot option, or 3,750 votes, with turnout on the Democratic side roughly a quarter of that in 2020.

New York does not have write-in options, so organizers of the “uncommitted” effort urged voters in the Democratic primary to leave their ballots blank instead. Blank ballots will not be reported in the initial, unofficial results of the primary, which showed Mr. Biden with more than 90 percent of tallied votes.

In New York’s Republican primary, Mr. Trump had above 80 percent of the vote, while Ms. Haley had 13 percent and Chris Christie, a former governor of New Jersey, scored more than 4 percent of the vote. He dropped out of the race in January.