Among those making the case, he claimed, are Sinema’s own Senate Democratic colleagues.

“It wasn’t Bernie, I’ll tell you that,” Gallego told CNN, referring to Vermont independent Sen. Bernie Sanders, who has said he’s open to backing a primary challenge to Sinema.

“It’s more than one” senator, he added before declining to say which of Sinema’s colleagues are privately hoping she will face an intraparty fight.

And he said that in the last several days the courtship has only intensified.

“To be honest, I have gotten a lot of encouragement from elected officials, from senators, from unions, from your traditional Democratic groups, big donors,” said Gallego, a seven-year House veteran. “Everything you can imagine under the sun.”