Utah Republican Sen. Orrin Hatch is “doggone offended” by the activists and voters standing between him and re-election, describing them as “radical libertarians.”

Hatch was first elected to the Senate in 1976. This year, major conservative groups announced their intention of defeating Hatch — who they deemed too moderate. FreedomWorks has reportedly spent at least $670,000 attacking Hatch this cycle.

But the long-time senator isn’t sitting on his hands. Hatch told NPR’s Howard Berkes, “These people are not conservatives. They’re not Republicans.”

“They’re radical libertarians and I’m doggone offended by it,” he said.

Hatch’s most prominent Republican challenger, former state Sen. Dan Liljenquist, appears to be underperforming expectations in local caucuses thus far. He lost his home caucus last month.

“I despise these people,” Hatch added, “and I’m not the guy you come in and dump on without getting punched in the mouth.”

If Hatch can secure 60 percent of the April 21 state convention vote, he would avoid a primary election. If he can not, the top two convention vote-getters will advance to a June primary. In a stunning 2010 convention vote, former Utah Sen. Bob Bennet was ousted after three terms in the Senate.

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