Republicans are favored to win a majority in the House of Representatives in Tuesday's elections, with the Senate rated a toss-up by nonpartisan election forecasters.
A crackdown on users impersonating Musk prompted Twitter to suspend comedian Kathy Griffin.
Musk also moved his personal residence from California to Texas, where there is no state income tax.
In April, Musk said on Twitter he believes that for the platform "to deserve public trust, it must be politically neutral."
Federal authorities are investigating Musk over his conduct in acquiring Twitter, the company said in a court filing last month.