A small group called Carolina Conservatives United, one of dozens organized loosely under the flag of limited government, low taxes and strict adherence to the Constitution, sent out images last week of a milk carton bearing Mr. Graham’s face and asked Gov. Nikki R. Haley to issue the state’s version of an Amber Alert to find its missing senator.

“Lindsey Graham has not been seen in the state of South Carolina for most of the last two years,” said Bruce Carroll, the chairman of the group.

Conservatives in South Carolina are eager to oust Mr. Graham, who has enraged the far right for, among other things, reaching across the aisle on immigration and supporting President Obama’s nominations for the Supreme Court.

“In order to run a successful grassroots campaign and defeat established incumbents with all their advantages, the candidate needs to be compelling,” said Matt Hoskins, spokesman for the Senate Conservatives Fund, a group that frequently targets GOP senators it views as too moderate. “More times than not, the candidates who defeat incumbents are exceptional candidates.”

The problem for tea-party activists is especially acute in South Carolina and Tennessee. It’s not that Sens. Graham and Alexander haven’t drawn challengers—Graham, in fact, has three of them. It’s that conservatives say the candidates who have emerged lack the profile, message, and skill to defeat an incumbent…

Three candidates have already stepped up to take on Graham in the Palmetto State: state Sen. Lee Bright, social-conservative activist Richard Cash, and Nancy Mace, who was the first woman to graduate from the Citadel. She is considered the strongest of the trio, but thus far, few consider her a serious threat to Graham, despite his outspoken advocacy for immigration reform.

“The early stages of her campaign indicate she might not be ready for prime time,” said Chip Felkel, a veteran South Carolina GOP strategist.

Kim Severson of the New York Times has more reporting today on Graham’s challenge in South Carolina, where tea party groups have taken to calling the hawkish Republican “a community organizer for the Muslim Brotherhood.” But despite their common antipathy for Graham, the 40-plus tea party and libertarian-leaning groups in the state must first hash out “a civil war of their own,” Severson reports, as they can’t decide on a common candidate.

The most promising choice is Nancy Mace, the first woman to graduate from the Citadel, but GOP strategists say the marketing executive, who has never run for office, “might not be ready for primetime.” Indeed, running against a well-funded and high-profile incumbent like Graham will be no easy task. He’s faced the tea party’s ire since its inception — it flushed him down a toilet in 2009, at least in effigy — but so far remains largely unscathed.

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South Carolina boasts more Tea Party politicians than any other state in the country, signifying that, if unified, a Graham challenger could rally significant support. Conservatives point to the election of Sen. Ted Cruz (R-Texas) as evidence that you can ride a wave of Tea Party support all the way to the Senate.

“South Carolina is a funny state,” Paul Anderko, president of the GPS Conservatives for Action PAC, told the Times. “Sometimes incumbents do go down in flames.”

And while the Bob Bennett example can be instructive — he was widely viewed as one of the Senate’s most reliable conservatives until he was ousted by conservatives in 2010 — it is hardly the rule. After all, just two years later in Utah, the supposedly similarly endangered conservative Sen. Orrin Hatch won in a landslide.

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U.S. Sen. Rand Paul is returning to South Carolina on Monday, making his second trip in as many months to the state that hosts the first presidential primary voting in the South.

Paul, a darling of tea party and other conservative Republicans, is coming back to South Carolina to take part in a fundraiser for U.S. Rep. Jeff Duncan, a friend from the GOP congressional baseball team…

The 50-year-old eye doctor was last here in late June, when he raised money for the state Republican Party and met with tea party-leaning activists. One of those meetings, Paul said, was with state Sen. Lee Bright, a Roebuck Republican who is mounting a primary challenge to U.S. Sen. Lindsey Graham.

Bright officially announced his candidacy earlier this month. During a winter tour around the state, he said Graham’s criticism of Paul’s 13-hour filibuster over the government’s use of drones pushed him toward running.

“If we don’t get behind Rand Paul and what he is trying to do and the Ted Cruz’s of the world, I don’t think we can survive,” Bright told Glenn Beck as the talk show host auditioned people to challenge Graham. “We’re at the tipping point.”

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