Abdul El-Sayed, the Democratic nominee for Michigan’s tightly fought US Senate race, has asked Democratic congresswoman Haley Stevens to stay away from his campaign events.

“I don’t want any distractions,” El-Sayed told reporters after a campaign rally, according to the New York Times. “It seems as though other folks are more interested in making this race about things that it’s not about.”

The two had planned to appear together on Sunday at a church service in Detroit.

The public rupture between the progressive El-Sayed and the more moderate Stevens, whom he defeated in a bitter primary, has cast Democratic tensions into the spotlight in one of the most consequential elections in the party’s campaign to retake control of the Senate.

Stevens endorsed El-Sayed shortly after he won the primary election in August, and planned to campaign with him on Sunday.

But Stevens had until now avoided appearing publicly with her former opponent, whom she has criticized publicly for weeks. Her fiance, Jason Turkish, has campaigned on behalf of Republican candidate Mike Rogers.

And just two days before they were scheduled to campaign together this weekend, Stevens demanded that El-Sayed denounce an outside group’s political ad that blamed higher prices on US support for Israel’s war in Gaza.

“Congresswoman Stevens seems intent on relitigating a primary that ended three months ago,” El-Sayed shot back in a statement, which noted that the American Israel Public Affairs Committee spent heavily to defeat him in the primary.

“Let’s all focus on the task at hand: that’s beating Mike Rogers, holding Trump accountable, and getting money out of politics, putting money in pockets, and passing Medicare for All,” the statement said.

The open feuding worries many Democrats, who see the tight race as a must-win for the party to win back the Senate.

“I have no idea what the hell Haley Stevens is doing,” Michigan state senator Mallory McMorrow told CNN Friday. “This is a moment where we have to recognize the stakes. People are not talking about ads. They are not talking about Haley Stevens. They are talking about the price of gas and groceries.”