A growing number of Democratic lawmakers have called for the expulsion of their colleague Eric Swalwell from the House of Representatives as he battles allegations of sexual misconduct that have upended his bid to be California's next governor.

Democrats said they would be on board with removing Swalwell if a Republican congressman, Tony Gonzales of Texas, who is also facing allegations of abuse involving a staff member, is removed from the chamber, too.

Virginia Democrat Eugene Vindman told CNN on Sunday: "We should not tolerate this behaviour. Representative Eric Swalwell needs to go."

Before the allegations surfaced Swalwell was projected as a frontrunner in the race for California governor.

Last month, Gonzales dropped his re-election bid after admitting to having an affair with a staff member. A House ethics panel is investigating his conduct.