Forget about the "middle class" cover story. More and more Republicans are straight up admitting they're pushing a tax give-away to the super rich because donors demand it.

Republicans have all been issued the same talking points as they try to ram through a once-in-a-generation tax bill with little or no public debate. And the feel-good rhetoric all revolves around the thoroughly debunked claim that the GOP’s planned give-away to the most wealthy, including large corporations, is really designed to help the middle class — the little guy.

But it’s not. Summing up the bill’s winners and losers, the New York Times recently listed as the winners, “Business,” “Multinational Corporations,” “The Rich And Their Families,” “Hedge Funds.”

And on Thursday, White House economic adviser Gary Cohn conceded the whole tax scheme is built around the discredited “trickle down” economic theory, where the GOP showers the very rich in new wealth and then they benignly share that wealth via investments and job creation.

Cohn also conceded that to date, CEOs of major corporations are the biggest fans of the Republican tax plan. (So much for Main Street.)

Still, most Republicans cling to the middle-class cover story because it just sounds better. But every now and then some let the truth slip out. On Thursday, Sen. Lindsey Graham (R-SC) was asked what the political fallout would be for Republicans in Congress if they failed to deliver a tax bill, just like they failed to replace Obamacare this year.

Graham offered up a dire prognosis: “The party fractures, most incumbents in 2018 will get a severe primary challenge, a lot of them will probably lose, the base will fracture, the financial contributions will stop, other than that it’ll be fine!”

So there it is: The South Carolina Republican isn’t worried that middle-class voters might lose out on a big (imaginary) tax cuts; he’s worried that deep-pocketed contributions from financial institutions will dry up.

The comment could be seen as an amazing revelation and slip of the tongue — remember that a political gaffe is defined as when somebody accidentally tells the truth — except other Republicans are admitting the same thing.

Last week, strident Trump supporter Rep. Chris Collins (R-NY) stressed that the GOP had to pass a tax give-away to the rich. “My donors are basically saying, ‘Get it done or don’t ever call me again,’” Collins said.

Collins and Graham aren’t even pretending to pay lip service to the idea that they’re elected to represent their voters. Today, they seem to have a constituency of one: wealthy donors.