Longtime Democratic strategist James Carville called for caution among Democrats amid their mushrooming enthusiasm following President Joe Biden’s decision to step down and endorse Vice President Kamala Harris as his replacement in the 2024 election.

Carville had been vocal in calling for Biden to ditch his reelection campaign following the president’s disastrous debate performance against Republican nominee Donald Trump in June.

Now Biden has done just that, Carville noted on Wednesday’s episode of MSNBC’s “Morning Joe” that there’s “a real change in mood in the party and around the country” with Harris now likely becoming the presidential candidate.

“But we got to be a little careful,” he told co-host Mika Brzezinski.

There’s “about 10% too much triumphalism going on,” and it’s “going to be a very difficult race,” he said. “It’s going to be very close, and I understand that people are feeling a lot better and excited, but that excitement has got to be tempered with realism, and the realism is she has a tough campaign going on.”

Carville had noticed a “real growth” in Harris, though, he said.

“You can just see the difference,” he added, noting Harris’ apparent increased confidence during her first official campaign rally in Milwaukee.

But it’s going to be “tough sledding ahead” for Democrats, he later warned.

Watch Carville’s full analysis here: