After three convincing Senate victories since succeeding Strom Thurmond in 1996, Republican stalwart Lindsey Graham of South Carolina could face his toughest Democratic opponent this November.

The presumptive Democratic nominee, Jaime Harrison, is considered a rising star in the state. The 44-year-old Yale University graduate, who previously served as the chair of the South Carolina Democratic Party, is expected to make a strong push in arguably the most conservative state in the country.

Graham, 64, a prominent Republican in the Senate, has become a close ally of President Trump after some initial public criticisms. He made an ardent defense of Trump’s Supreme Court nominee Brett Kavanaugh in September 2018 and more recently defended Trump during his impeachment trial in the Senate.

Prior to becoming a loyal Trump backer, Graham made efforts to align himself as a moderate Republican open to bipartisan cooperation, despite expressing hawkish views. He was a critic of Trump during the 2016 presidential race and took offense to Trump’s comments about his late friend and mentor John McCain.

Shifting opinions from Graham may mean his road to another Senate victory could be more difficult, which could prompt more fundraising on Graham's behalf. The DNC, meanwhile, is no doubt excited about the prospect of an up-and-coming candidate like Harrison who can potentially flip a Senate seat in a red state, particularly after the upset victory of Sen. Doug Jones of Alabama in 2017.

Harrison appears to be seizing on Graham's perceived dip in popularity, often writing #SendLindseyHome on his Twitter posts. Harrison, an African-American, hopes to rally minority voters in South Carolina, and also attract other Democrat-leaning demographics, such as college-educated suburban voters.

“I think [the Democratic spirit] is alive and well all across the South. The real question is getting people to believe that it’s possible here,” Harrison recently told Mother Jones. “People have a little sliver of hope, and now it’s important for me to take that sliver and turn it into a roaring flame.”

South Carolina voters still have some time to get to know Harrison, who was raised by his mother and grandparents in the small town of Orangeburg. He believes that his modest background will appeal to working-class people. Harrison currently works as associate chair and counsel of the DNC.

Harrison has also worked for South Carolina Rep. Jim Clyburn, an African-American icon whose endorsement recently helped former Vice President Joe Biden win the Democratic primary in the state.

“We have folks in desperate need of healthcare, rural broadband access, and a representative in Washington who's looking out for them, not his own political aspirations,” Harrison tweeted, referring to Graham.

But Harrison remains a clear underdog, as Graham has a 48% approval rating and a 36% disapproval rating, according to Morning Consult. Harrison is also outmatched in terms of fundraising, having only raised $4.7 million in comparison to Graham’s war chest that is over $10 million.

For his part, Harrison raised $3.5 million in the final quarter of 2019, which is more than any candidate has brought in for a single quarter in South Carolina history.

Fundraising aside, no Democratic candidate has managed to win a statewide election in South Carolina since 2006. Graham, meanwhile, is coming off a 57.5%-42.3% win in 2008 and a 55.3%-38.8% win in 2014.

“On the whole, South Carolinians are happy about the direction of our state and support our elected leadership on the state and federal levels,” Walter Whetsell, a GOP campaign consultant and president of Benchmark Research, told The State newspaper in November. “Additionally, voters here support his strong stance on illegal immigration and want to see the border wall completed.”

Harrison is seeking to get a stronger turnout by registering voters, as opposed to converting swing voters, a strategy that helped elevate Democrats Robert "Beto" O'Rourke and Stacey Abrams into the national spotlight in 2018. While O'Rourke and Abrams came up short, the results were far better than most pundits initially expected.

Harrison, who struggles with name recognition against a well-known incumbent, is also making the rounds on national media, one day after Biden's historic victory in the presidential primaries.

"Everybody knows Lindsey, but everyone doesn't like Lindsey," Harrison told Chris Matthews of MSNBC. "That's how I'm going to beat him."

South Carolina congressional elections will take place on Nov. 3.