Lindsey Graham, a Republican senator, has complained he is getting "killed financially" by his Democratic rival, Jaime Harrison, who has seen a surge in donations following death of the late Supreme Court Justice, Ruth Bader Ginsburg.
Mr Gramham, whose role as Judiciary Committee chair puts him at the heart of GOP efforts to replace Ginsburg before November's election, bemoaned the reported improved financial muscle of his rival, saying that the donors "hate my guts".
"My opponent will raise $100 million in the state of South Carolina,” Mr Graham, 65, told Fox News on Thursday. “The most money ever spent in the history of the state on a Senate race in this state was by me in 2014 when I spent $13 million.”
It was not immediately clear what figure Mr Graham, an ardent supporter of president Trump, had been alluding to. Recent reports have suggested that Mr Harrison, 44, pulled in around $9 million worth of donations in the 72 hours following Ginsburg's death last Friday.
According to federal election spending records, Mr Harrison raised $28 million in June, compared with his rival's $29 million. It remains to be seen how much more money Mr Harrison can pull into the coffers before November's election, but the $100 million touted by his rival seems excessive.
The death of Ginsburg, a liberal icon who spent almost three decades serving on the highest court in the land, has proved to be somewhat of a curveball in an election already described as one of the most important in living memory.
Mr Trump, 74, has vowed to replace Ginsburg with a conservative justice, a decision that may well reshape the court for a generation. If the president and GOP press ahead with the plan, it would decisively tilt the ideological balance of power in the Supreme Court. The court's rulings have implications for some of the most important and hottly contested US laws.
Mr Graham, who appeared on Fox News last week to issue a rallying cry for more funds of his own, faces a battle to hold onto his seat in the solidly red state, which the president won easily in 2016. A Quinnipiac University poll from earlier this month showed the pair tied on 48 per cent.
Responding to the incumbents plea for help, Mr Harrison taunted the GOP politician on Twitter. "Anybody else get the sense that Lindsey Graham just realized he's going to lose on November 3rd?" he said.
He later tweeted the hashtag "#LindseyGrahamIsLosing" as he called for supporters to "keep it that way" by donating more money to his campaign.