U.S. Sen. Rand Paul is coming to the defense of a fellow Kentucky Republican who is being threatened with a primary challenge by the national GOP in 2020.

As the Courier Journal first reported, U.S. Rep. Thomas Massie is beloved among libertarian but more establishment figures are searching for someone to boot him out of Congress.

In an interview, state Rep. Kim Moser, R-Taylor Mill, said she been approached about a possible bid against the congressman, who has been dubbed "Mr. No" by critics for regularly opposing overwhelmingly bipartisan measures.

Moser said that there are concerns about Massie's representation in the 4th Congressional District.

"Some of the issues that he focuses on really don't seem to affect the day-to-day lives of the people I work with," she said.

Paul, who ran for president in 2016, used his campaign Twitter account to declare that he has Massie's back, however.

"My friend (Thomas Massie) stands up for Kentucky and is one of the few people who can be counted on to defend your liberty," Paul tweeted. "He does what he said he would do — every day. He has my full support."

Massie has been in Congress since 2012, and represents a district that spans from parts of Louisville to Ashland. It also includes the Cincinnati suburbs in Northern Kentucky, which is a hotbed of conservative activism.

"If the Courier Journal knows about a viable plan from the swamp to take me out, please let me know, because I don’t," Massie said in a statement. "In the meantime, I’ll keep draining it."

More:National Republicans may be maneuvering to unseat Kentucky's conservative darling, Massie

Moser serves as chairwoman of the state House Health and Family Services Committee who was among the class that helped Republicans seize the Kentucky House for the first time in nearly a century. She is the daughter of former gubernatorial candidate Floyd Poore, who sought the Democratic nomination in 1991.

Moser cited many concerns about Massie's votes, such as his stance against a $19 billion disaster relief package and a federal addiction program that directed $6.3 billion to speed up drug treatment.

Moser told Kentucky Health News in a February interview that she hasn't ruled out running for higher office.

"This wasn’t the plan and that’s not my plan, but you never know what opportunities come your way," she said at the time. "And again, if I feel like I can offer something, that is why I would do that."

Two sources, who requested anonymity, told the Courier Journal that U.S. Rep. Elise Stefanik, R-N.Y., is among those looking for a challenger for Massie. Stefanik, who represents upstate New York, has made putting more women in Congress a personal passion.

But a Stefanik spokeswoman denied she was dabbling in Bluegrass politics, saying in a statement the the congresswoman's political action committee, "has a firm policy of not recruiting against or endorsing against Republican incumbents."

Moser declined to comment when asked if Stefanik was among those who had approached her about running next year.

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Other Massie allies spoke out against the threat of a primary challenger as well. In a tweet, the political arm for the conservative Club For Growth said it hopes Stefanik isn't meddling in Kentucky, but that if she "recruits a primary challenger to Massie, we will respond in kind."

Massie is beloved among libertarians for his stances against military intervention and federal spending. Activists with the tea party movement described him as the one GOP lawmaker in Kentucky's congressional delegation who respects the Constitution.

"Hal Rogers is the 'king of pork'; Brett Guthrie has voted for more spending than any other Kentucky Congressman; Jamie Comer has separated himself from the establishment on a few occasions but typically follows the herd. Andy Barr is establishment all the way, what ever the leadership wants, he's only too happy to give it to them, even if its unconstitutional," said Scott Hofstra, a United Kentucky Tea Party spokesman.

"Congressman Massie is the only real representative the citizens of Kentucky have in Washington," he added.

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Massie has gained national attention, however, for being among a handful of House members who vote against various bipartisan measures whether innocuous or consequential.

This year, for instance, he opposed renaming a post office after the late Rep. Louise Slaughter, a native Kentuckian who represented New York for three decades. He also was among a group of seven members who rejected a bill guaranteeing back pay for federal workers hit by the government shutdown this year.

Reporter Phillip M. Bailey can be reached at 502-582-4475 or pbailey@courierjournal.com. Support strong local journalism by subscribing today: courier-journal.com/philb.