A former staffer to Sen. Joseph Biden (D-Del.) acknowledged this week he is eyeing a primary challenge to Rep. Karen McCarthy, the Missouri Democrat who recently returned to her Congressional duties after undergoing alcohol abuse treatment.

Jamie Metzl, 34, a senior fellow and coordinator for homeland security programs at the Council on Foreign Relations, said he is “considering” a bid but has not made a final decision. The Kansas City, Mo., native would not comment about who he is consulting with about a potential campaign, nor would he lay out a timeline for, or the factors influencing, his decision.

“I’ve been approached about running, and I am considering it,” said Metzl, who has never before sought political office. “But I have made no decisions.”

When pressed for details about a potential campaign, Metzl would say only: “Right now I’m just talking to people. I’m honored to have been approached and I’m considering it.”

McCarthy, a five-term Member who sits on the powerful Energy and Commerce Committee, returned to Congress more than two months ago after undergoing alcohol dependency treatment. She has not formally announced her re-election plans but has said she is committed to a sixth term in the House.

Matt Nerzig, a top aide to McCarthy, wouldn’t address Metzl’s possible bid, but did say Tuesday of McCarthy’s plans: “She’s running.”

The Missouri lawmaker’s office has suffered the loss of several staff members in recent months, including longtime Chief of Staff Phil Scaglia, who resigned the post nearly two weeks ago. When approached by Roll Call, Scaglia initially wouldn’t rule out a potential primary challenge to his boss but has since said he’s ruled out the option completely. He plans to pursue two consulting ventures.

“I’m not running against her,” Scaglia told The Kansas City Star. “The door is closed.”

With Scaglia out of the bidding, Metzl appears to be the first possible primary opponent for McCarthy, who represents a strongly Democratic district.

Metzl formerly worked as the deputy staff director of the Senate Foreign Relations Committee under Biden from 2001 to 2003, at the State Department and at the National Security Council.

Metzl said he was first approached about running against McCarthy after his June 29 appearance on NBC’s “Meet the Press,” in which he discussed national security issues and a report he helped compile about shortfalls in funding for emergency responders.

While Metzl was largely mum about the details of a potential bid, he told the Kansas City Jewish Chronicle in a June 13 article: “At some point in the future, I’d like to run for office or to work with a Democratic administration once a new administration is voted into office.

“I have gotten so much out of public service and I’m deeply committed to public service. I’m always looking for new opportunities and new ways of serving.”