Mark Sanford, a former South Carolina governor and U.S. representative, on Thursday joined a crowded field of Republicans seeking the party's nomination for the U.S. Senate seat formerly held by the late Sen. Lindsey Graham.

Sanford, 66, who made a longshot bid for the 2020 Republican presidential nomination, is the ninth person to either file or declare a candidacy to replace Graham, 71, who easily won the June 9 primary before dying July 11 of an aortic dissection.

The special election is Aug. 11 and a runoff will take place Aug. 25 for the top two finishers if no one wins a majority of the vote.

Sanford announced his bid in a video posted on X, with a pitch focused on the national debt and the financial burden being left to future generations.

Sanford opened his video by reflecting on Graham's death and the brevity of life, recalling that his father was diagnosed with ALS, also known as Lou Gehrig's disease, when he was in high school.

"Lindsey's death is a reminder to all of us of how short and precious life is," Sanford said. "And this notion of all of us having just a little time has always hit me hard."

Sanford argued that Americans have a responsibility to protect what they inherited and leave the country better for those who follow.

"We're stewards of our lives and the things that we love are just a short time. I'm now a dad and a grandad, and I'm worried for our children because for the first time, America is borrowing for the future faster than we're building it," he said.

"We'll add about a trillion dollars to the national debt over the next 100 days, and if left unaddressed, that debt will crush our economy, it will wipe out our savings, and it could even destroy our republic," Sanford continued.

"Our ability to afford things, inflation, and the way people struggle to build a life are but symptoms of spending beyond our means as a country.

"We're at a tipping point, and that's why I decided to run for the U.S. Senate."

Sanford represented South Carolina's 1st Congressional District from 1995 to 2001 and from 2013 to 2019. He had been a critic of President Donald Trump's first administration, prompting Trump to back a primary challenger in 2018.

Sanford lost that Republican primary. Democrat Joe Cunningham won the general election in an upset before Republican Nancy Mace defeated him in 2020.

Earlier this year, Sanford flirted with a return to Congress when he launched a surprise comeback bid for his old seat in the 1st District, which is still held by Mace, after the congresswoman decided to run for the Republican gubernatorial nomination.

He dropped out of the race 30 days later, saying his time might be better spent launching an advocacy group and that his heart wasn't in it.

But his exit came too late to take his name off the ballot. Sanford finished fourth in the primary.

Jenny Honeycutt and Mark Smith advanced to a June 23 runoff after neither received a majority of the vote. Honeycutt won and will face Democrat Nancy Lacore in November.

Gov. Henry McMaster appointed Graham's sister, Darline Graham, to fill her brother's seat for the rest of his term.

After being encouraged to run and endorsed by President Donald Trump, she announced Monday that she will seek a full six-year term in the special election.

Others who have announced bids include Reps. Russell Fry and Ralph Norman.