'Big mistake': Chris Matthews incorrectly ID's GOP Sen. Tim Scott as Dem running against Sen. Lindsey Graham

MSNBC host Chris Matthews made what he called a "big mistake" on air Friday evening while interviewing Democratic Senate candidate Jamie Harrison, when he played footage of GOP Sen. Tim Scott at a Trump rally and mistook the Senator for Harrison.

To make matters even more cringeworthy, Scott was seen in the footage standing next to fellow South Carolina Republican Sen. Lindsey Graham — the man Harrison is hoping to unseat.

What are the details?

In the MSNBC video shared by a Politico reporter on Twitter, Scott and Graham can be seen smiling in attendance at President Donald Trump's rally in South Carolina that night while Matthews tells his guest, "Jamie, I see you standing next to the guy you're going to beat right there, maybe. Maybe, maybe. Lindsey Graham."

At that point, Fox News reported, "Democratic strategist Adrienne Elrod and network correspondent Trymaine Lee both chimed in to alert Matthews that he'd made a mistake, but it took several seconds for him to realize the mixup."

"Who's that?" Matthews asked, before Lee repeated again, "That's Tim Scott."

"Oh! The other senator, Tim Scott, what am I saying? Big mistake," the "Hardball" host said before telling Harrison, "Mistaken identity, sir, sorry. Tell me how you're going to beat Lindsey. Everybody knows Lindsey."

Harrison took the flub in stride, smiling and laughing before answering, "Everybody knows Lindsey, but everybody doesn't like Lindsey Graham. And that's how I'm going to beat him, Chris."

The challenger added, "This is a guy that you can't trust. This is a guy that doesn't have a moral compass. And all he's focused on is Washington, D.C. games. And at the end of the day, the folks in South Carolina are going to give Lindsey Graham a one-way ticket, maybe not back here to South Carolina, but possibly to Mar-a-Lago. We're fed up."

According to Harrison's campaign website, he is the first African American chair of the South Carolina Democratic Party. He is running to beat Sen. Graham in this fall's election.