Republican allies of Mr. Trump say that greater scrutiny is necessary to detect even rare cases of illegal voting and to restore public confidence in elections. Democratic lawmakers and many experts on elections administration say it is Mr. Trump’s own rhetoric that is corroding trust in elections, and that the process has been subjected to exhaustive scrutiny since he refused to accept his defeat in 2020. (Mr. Trump has generally not questioned the legitimacy of the elections he won. After his 2016 victory, he established a commission to look into voter fraud as a possible explanation for his popular vote loss; the commission found no evidence of fraud.)