An April 2015 Winthrop University poll of nearly 1000 residents of South Carolina found that close to 55 percent of respondents “would not consider voting for” Graham as a presidential candidate. Of the 13 other Republican nomination hopefuls listed for the respondents, the only person South Carolinians were less likely to consider voting for was Donald Trump. Thirty-seven percent said they would consider voting for Graham, but Jeb Bush, Senator Ted Cruz, Mike Huckabee, Senator Rand Paul, Rick Perry, Senator Marco Rubio, and Governor Scott Walker were all more likely to be considered.

When confronted with the results of that poll in April, Graham apparently “shrugged off the numbers,” according to The Washington Post. He told the paper, “If I’m on the ballot, I’m going to win South Carolina.” It’s not a ludicrous assertion. The effect of home-state loyalty in presidential elections is statistically significant, though only under some circumstances. And Graham’s 2014 victory could reasonably give him a sense of security at home: Despite early concerns that Graham was vulnerable to a more conservative challenger because of his standing as a bipartisan compromiser, he won with nearly 55 percent of the vote.

However, Graham’s success last year may say less about his popularity than a lack of a strong alternative. In 2014, the most viable conservative Republicans had taken themselves out of the contention. Jim DeMint left the U.S. Senate to run a conservative advocacy group, and his appointed successor, Tim Scott, was the one rival that Graham would have had to sweat—had DeMint not retired early. In the end, Graham’s challengers in 2014, individually, didn’t stand a chance against the senator. The South Carolina presidential primary, by contrast, will be contested by some of the most established conservative politicians in the country.

So while Graham has a home-state advantage in South Carolina, he also has a decent chance of losing there, especially if he continues to play up his bipartisan track record and is perceived as a Washington insider. His constituents might generally (58.2 percent) approve of how he “is handling his job as a United States Senator,” according to the Winthrop poll, but that doesn’t necessarily mean those who re-elected him last November think he would make a good president, or that he could be a viable conservative candidate. His perceived successes as a senator could even hurt his chances at home; his constituents may not want to risk losing Graham’s advocacy on their behalf in the Senate, especially if they’re also intrigued by the prospect of a different presidential candidate, like Walker or Bush. And if Georgia Secretary of State Brian Kemp's push for a “SEC” primary on March 1 continues to draw in southeastern states—the idea being to increase the region’s national influence by moving primaries up to that date—then a Tea Party candidate like Cruz could build momentum by winning a couple of southern states, and may have a shot at taking South Carolina from Graham.