Adam Putnam and Alan Grayson,

two former rising political stars, are flaming out, writes Scott Maxwell.

As far as Donald Trump rallies go, the scene at the Tampa fairgrounds Tuesday wasn’t particularly remarkable.

The place was packed and energized. And the crowd was cloaked in red, white and blue — a flag dress here, a “F*** the media” T-shirt there and MAGA hats everywhere.

What was remarkable, though, was that virtually everyone there was cheering for the downfall of Adam Putnam.

They all wanted to see the state’s agriculture commissioner — a lifelong Republican who was once the party’s rising star — go down in flames.

This isn’t how things were supposed to happen.

Putnam, after all, followed all the rules for an aspiring GOP politician.

He started running for political office at 22. He kept running for the next two decades. And he kissed all the right rings along the way — those worn by the state’s business leaders, evangelicals and the NRA. He went hunting with Big Sugar. He decried the EPA. Rarely did he make waves.

Yet, from the moment Trump endorsed Putnam’s primary opponent, Republican Congressman

Ron DeSantis, Putnam’s onceballyhooed gubernatorial campaign has been in free-fall.

It’s reminiscent of 2010, when everyone thought Attorney General

Bill McCollum — another longtime party loyalist — would cruise to victory until Rick Scott used tens of millions of his own dollars to shake things up.

Veteran Republicans thought Scott’s campaign was a joke … until they decided to join it.

I still remember sitting next to a GOP lobbyist at a Tiger Bay political club event in late summer of 2010. The lobbyist and attorney had been a McCollum ally and fundraiser. But during the meeting, he got the results of yet another poll that said Scott was surging ahead — and decided it was time to jump ship. He did so that afternoon.

That’s about where we are right now. And if Putnam’s allies start bailing, the journey from coronation to annihilation will be complete. Establishment support is what’s keeping him afloat.

In some ways, this shouldn’t be a surprise. In recent cycles, Republicans in Florida have craved the same thing Republicans nationwide craved — the outsider over the insider. It’s the party’s recent theme: Shake things up. Burn things down.

And unless something changes in the next four weeks, it looks destined to happen again.