Retiring Reps. Mike Rogers (R-Mich.) and Dave Camp (R-Mich.) may back Rep. Justin AmashJustin AmashOvernight Defense: House votes to renew surveillance program | More drones, troops headed to Afghanistan | Former officers urge lawmakers to curb Trump's nuclear powers Overnight Tech: House votes to reauthorize surveillance powers | Twitter on defensive after Project Veritas video | Senate panel to hold hearing on bitcoin Overnight Cybersecurity: House votes to renew NSA spying | Trump tweets spark confusion | Signs Russian hackers are targeting Olympics | Bannon expected to appear before House Intel panel MORE's (R-Mich.) primary opponent, and none of the rest of the Michigan delegation is supporting Amash, according to the Detroit News.

Rogers, a longtime Amash foe, told the paper that he's "likely" to support businessman Brian Ellis, while Camp said he was also open to backing Ellis in the race.

"I think he'd far better represent that district and the values that they hold true," Rogers said about Ellis.

"I don't really want to be critical of Justin in the press," Camp said of Amash after saying he'd consider donating to Ellis if asked. "But I think his votes speak for themselves. I haven't always agreed with everything."

No one in of Michigan's GOP delegation has even donated to Amash, making him the only member not to have received money from another this election cycle.

Amash, a libertarian who's sparred repeatedly with House leadership, has long been at odds with much of Michigan's delegation. Still, Michigan observers say he has the edge in the primary against the self-funding Ellis.