The main point from Donald Trump’s interview on ABC’s Good Morning America: he has started taking Ben Carson more seriously as a threat in the Republican primary race. For one, Trump showed up in person, a choice that he has only recently made rather than phoning in for interviews on television shows as he did for most of his time as a front-runner. Trump also took aim at Marco Rubio in this interview with George Stephanopoulos, who has begun to assert himself and move away from the pack, but took a swipe at Jeb Bush, too:

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Republican presidential candidate Donald Trump ripped into his Republican rivals today, saying Ben Carson doesn’t have the experience or the temperament to be president.

“It’s not his thing. He doesn’t have the temperament for it,” the New York real estate mogul told ABC News’ George Stephanopoulos on “Good Morning America.” “I think Ben just doesn’t have the experience.”

Trump also blasted Marco Rubio, who’s emerging from the pack as an establishment alternative to Jeb Bush. “I’m not a fan. I think he’s overrated,” he said, adding that Russian President Vladimir Putin “would eat him alive.”

He also criticized Bush, saying he should “absolutely” drop out of the 2016 race. “He doesn’t have a chance,” Trump said today.

An attack on experience is at least somewhat curious for Trump, who like Carson has never held political office. Both are neophytes in that sense. Trump has plenty of executive experience in the private sector, for better and for worse, but otherwise has exactly the same kind of office in public service as Carson — and less than Rubio or Bush. Part of the reason Trump and Carson are riding high in the polls is due to that lack of political experience, as anti-establishment fervor has voters looking for outsiders rather than experience in the primaries of both parties.

An argument on temperament is even more curious. Carson’s temperament is famously, perhaps even notoriously, calm and even-tempered. Trump’s the candidate that throws around insults — he calls Jeb Bush a “stiff” later in the interview, garnering laughs from the crew on the set — and talks about how great and fabulous he himself is in relation to everyone else around him. The question of Trump’s temperament has come up much more often than Carson’s, although it hasn’t exactly slowed Trump’s rise. Bringing that up as a legitimate issue in the race has more than a little potential for backfire.

Trump’s right, though, that the polling is very fluid at this point. Carson has definitely surged, but Trump is actually in about the same position as three months ago when he was the lone frontrunner in the RCP average:

We saw the same dynamic in our Hot Air/Townhall poll among Republican primary voters, taken after the most recent debate. Trump’s numbers only declined slightly, and within the margin of error; it was a surge from Carson that put him into the lead. From the above graph, it appears that Carson has gotten his votes from the deflation of the Carly Fiorina bubble since mid-September. Rubio and Ted Cruz have improved their position, perhaps largely from Bush’s slide over the same period. The votes are split between the outsiders and … the nearly outsiders, as one might consider both Rubio and Cruz, each of whom have only been in the Senate for less than a single term. The governors, a class that held so much promise at the beginning of the year, are all but gone from the mix.

So governing experience isn’t exactly a winning point anyway, and temperament perhaps only marginally more so. Voters in the Republican primary want change, and at this point, all four of the candidates with significant support fit that mold.