Dr. Abdul El-Sayed, the Democratic nominee in Michigan's pivotal Senate race, has struggled to move past criticism of his relationship with streamer Hasan Piker. El-Sayed says he disagrees with Piker on many things and won't campaign with him this fall, but has resisted calls to fully disavow him.

This week, calls grew after Piker said the U.S. had caused more terror than the group behind the Sept. 11 attacks. El-Sayed swiftly rejected the assertion. Republican nominee Mike Rogers said "enough is enough" and called on El-Sayed to "condemn Piker once and for all."

The episode underscores the challenge Piker poses for El-Sayed, whose race could decide Senate control. Piker has sway with progressives who powered El-Sayed's primary campaign, but other Democrats are appalled by Piker's criticism of the U.S. and Israel. Rogers has used Piker's commentary to cast El-Sayed as outside the mainstream.

El-Sayed said he campaigned with Piker to reach his audience. Piker told Axios the U.S. caused more terror than Al Qaeda "pound for pound." El-Sayed disagreed, saying he doesn't give much weight to a social media streamer's statements.