Can a relatively unknown Democrat unseat one of Trump’s closest Senate allies?

Polls reveal Democrat Jaime Harrison Polls has been tying with Lindsey Graham in recent weeks

Senator Lindsey Graham, a Republican from South Carolina and chairman of the Senate Judiciary Committee, listens during a Senate Judiciary Committee confirmation hearing in Washington DC, USA, OctoberShow more

The spotlight shone on Senate judiciary committee chairman Lindsey Graham on Monday at confirmation hearings for Amy Coney Barrett, President Donald Trump’s nominee to replace the late justice Ruth Bader Ginsburg on the Supreme Court.

Mr Graham staunchly defended the Republican Senate’s decision to advance Ms Barrett’s nomination amid a major election, despite Democratic objections.

But he has other things to think about, chief among them the unusually close race against his Democratic opponent, Jaime Harrison, for his spot in the Senate.

Mr Harrison’s campaign reported on Sunday that he has raised $57 million between July and September in his bid to unseat Mr Graham – the largest haul for any Senate race in US history.

Polls in recent weeks have put Mr Harrison in a tie with his opponent, which is highly unusual in the reliably Republican state of South Carolina that Mr Graham won by nearly 16 per cent in 2014.

Mr Graham has served in Congress since 1995; Mr Harrison has never held an elected office.

A former lobbyist for the Podesta Group, Mr Harrison was chairman of the South Carolina Democratic Party from 2013 to 2017, and is now an associate chairman at the Democratic National Committee.

He is running against his Republican opponent as a centrist.

Mr Graham was widely considered to be an establishment centrist for much of his political career, but has veered sharply to the right since Mr Trump entered the White House.

Since then, he has rarely disagreed with the president, except over certain national security issues.

Mr Graham joined seven other senators in 2013 to write a major bipartisan immigration reform bill, and attacked Mr Trump as “a race-baiting, xenophobic, religious bigot” over his 2015 proposal to ban all Muslims from entering the US.

He eventually lined up behind Mr Trump’s his efforts to build a wall on the US-Mexico border and the White House’s travel ban against several Muslim-majority countries in 2017.

The US polling aggregator FiveThirtyEight gives Mr Harrison only a 25 per cent chance of ousting Mr Graham.

FiveThirtyEight's Perry Bacon Jr explains that "the closeness in the polls may overstate" Mr Harrison's odds of ousting Mr Graham because of his uphill battle to sway the state's white Republican voters.

“Harrison, like previous Democrats who have run in South Carolina, had a fairly easy path to 45 per cent [combining the state’s black voters and white Democrats] but has a much, much harder time getting to 50 per cent,” Mr Bacon wrote on Friday.

During a debate with Mr Harrison on Sunday, Mr Graham said systemic racism did not exist in South Carolina because “you can be an African American and go to the Senate".

He gave as evidence his fellow South Carolina senator Tim Scott, a Black Republican.

“You just need to be conservative, not liberal.”

Mr Harrison, who is black, immediately hit back on Twitter.

“Lindsey Graham finally said the quiet part out loud," he said.

"He only cares about South Carolinians who belong to his political party."