In one of the last red-state bastions of appreciation for appropriations, Sen. Thad Cochran’s decision to seek re-election sets up a unique test for hard-line conservative groups that have targeted incumbents over the past few cycles.

The six-term Republican and veteran appropriator is beloved in Mississippi for his efforts to direct federal funding to a state in need — especially in the aftermath of Hurricane Katrina — so labeling him the “king of pork” won’t necessarily be a winning argument, even in a low-turnout Republican primary.

“If you can’t identify a Bridge to Nowhere, which I think they’re going to be hard-pressed to do, then you better come with something better than that,” said Hayes Dent, a Mississippi-based lobbyist.

Cochran surprised even some state party insiders when he announced Friday that he would run for another term. Now his record of bringing home the bacon for the state’s various needs will be weighed against an onslaught of criticism from conservatives over his Senate tenure.

He faces his most competitive challenge since 1984 from state Sen. Chris McDaniel, whose entrance in to the race in October brought immediate endorsements from ideological outside groups that are interested in electing more senators like Ted Cruz of Texas. Cruz was a central figure during the 16-day federal government shutdown in October.

“The question will be, in today’s electorate, how many people are willing to ignore [Cochran’s work for the state] relative to the federal debt problem,” said John Keast, a former chief of staff to Sen. Roger Wicker, R-Miss. “Will they make Thad Cochran the poster child? The McDaniel folks are certainly going to try, but I’m confident Mississippians aren’t going to agree with McDaniel’s approach.”

Mississippi has a heritage of incumbents building up seniority and being sent back to Capitol Hill for several terms. The state has elected just five senators since the end of World War II.

The downside to Cochran’s breezy re-election bids is that he hasn’t had to run a competitive race in 30 years, and Cochran allies concede he faces a tough fight. Although McDaniel is relatively unknown across the state, there are already indications that the race will split the party, even among the conservative wing.

“There are some in the conservative coalition that will be working hard for Chris McDaniel,” said Pat Bruce, head of the Madison County Conservative Coalition, who was complimentary of both candidates. “But then others will be working for Sen. Cochran because of what he’s done for us over the years.”

In the past two months, groups such as the Club for Growth, Senate Conservatives Fund and the Madison Project launched TV and radio ads in Mississippi to help raise McDaniel’s name recognition. Now that Cochran has confirmed he is running, the groups are likely to turn their focus back on Cochran, criticizing his votes in favor of bailouts and raising the debt ceiling.

Given Cochran’s leadership in landing federal disaster relief dollars after Katrina — a popular move in the state — leaders of the Madison Project told CQ Roll Call on Friday that they won’t necessarily be targeting his earmarks. Their argument is that there is someone else in the race willing to fight harder to defund Obamacare and who won’t support bailouts of any kind.

McDaniel responded to Cochran’s re-election announcement by noting that the race is about more than just a single Senate seat.

“Sen. Cochran has had a long and distinguished career representing the people of Mississippi,” McDaniel said in a statement. “I look forward to a positive campaign based on the future of our state, our country and the Republican Party. As a strong conservative, I will fight to bring those values to Washington.”

Cochran allies are preparing for a costly and negative campaign.

“In this campaign finance environment, these groups are able to come in from out of state and promote somebody, and there’s no question they’ll start attacking Sen. Cochran soon,” Republican operative Henry Barbour said. “If they think they can come into Mississippi to tell us how to vote, I guarantee you we’re ready to go toe to toe. We look forward to the fight.”

Cochran supporters also note that his work in the Senate — from agriculture to water to education to infrastructure — is evident every time voters drive down an interstate. And despite lackluster fundraising so far this year, Cochran, 75, is well-positioned with $804,000 in cash on hand as of the end of September.

“I think that the strength of Cochran has been his reputation to the state as someone who responds to the state’s needs,” Mississippi-based GOP consultant Brian Perry said. “And I think he’s going to be able to raise the money necessary to run a strong campaign.”