Sen. Lindsey Graham (R-S.C.) is virtually tied with his Democratic challenger, Jaime Harrison, according to a CBS News-YouGov poll released Sunday.

The candidates are in statistical dead heat, with 45 percent of likely voters backing Graham and 44 percent backing Harrison.

An additional 9 percent of likely voters said they are not sure who they will vote for in the Senate race. 

How Graham, the chairman of the Senate Judiciary Committee, handles the upcoming confirmation hearing for Amy Coney Barrett, President Trump’s Supreme Court nominee, may not move the needle much for him, CBS noted. Nearly half of voters, 45 percent, said whether Graham votes to confirm Barrett won't affect their Senate vote, and the rest are divided along partisan lines, according to CBS. 

The poll also found that 46 percent of likely voters said Graham agrees with Trump "too much," while 36 percent said the senator agrees with the president “about the right amount,” and just 18 percent said he agrees with Trump “not enough.”

The CBS survey is the latest to show a tightening race in South Carolina, and Harrison has placed himself as a formidable challenge to Graham, raising millions in his campaign against the three-term senator. 

Graham himself acknowledged last week that he is "getting killed financially" by Harrison. 

The Democratic challenger is also leading a Republican incumbent in North Carolina. Democrat Cal Cunningham has drawn support from 48 percent of likely voters, compared with 38 percent who said they support Sen. Thom Tillis (R-N.C.), according to the CBS-YouGov poll.

Tillis voting for Trump’s nominee would please most Republicans but appears to be a slight net negative among independents, according to CBS. 

In Georgia, Sen. David Perdue (R) holds a lead over his Democratic challenger, Jon Ossoff, at 47 percent to 42 percent, based on the CBS-YouGov poll. 

Republicans are facing a number of close Senate races that could be swayed by the battle over confirming Trump’s Supreme Court nominee ahead of the election. Democrats are looking to pick up three or four Senate seats, depending on which party wins the White House, to gain control of the upper chamber. 

The surveys were conducted on behalf of CBS News by YouGov between Sept. 22 and Sept. 25. They are based on a sample of 1,164 voters in Georgia, 1,213 in North Carolina and 1,080 in South Carolina. The margins of error are 3.3 percentage points in Georgia, 3.6 percentage points in North Carolina and 3.8 percentage points in South Carolina.