Among some of the president’s advisers, jitters stem from a recent internal Republican poll discussed among officials in the White House and the Trump campaign this week that contained an alarming range of signs about the vacancy, according to people who reviewed it. The poll — conducted over the weekend among about 1,500 likely voters in 17 swing states, including Arizona, Wisconsin, Florida, North Carolina and Pennsylvania — showed that 51 percent of voters said they trust Biden more than Trump to handle the vacancy, while only 43 percent said they trusted Trump.

The document also showed that only 28 percent of the voters said they would be more likely to vote for Trump if a replacement is confirmed, while 38 percent said they would be less likely. And 52 percent said the Senate should hold hearings after the election, while 41 percent said it should hold hearings before the election.