It all comes down to marketing versus math.

In this era when members of Congress can build a huge social media following and raise tons of cash online, they don’t really need to toe the line of a political party.

That means they can become a celebrity who nonetheless has little clout in what actually happens in Washington.

Or they can go a different route, which involves negotiation, compromise, often incremental progress – all the things that the strongest partisans hate about government.

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But that’s the only route for getting things done – if indeed that’s your goal. It’s called getting to 218 – the magic number that Kevin McCarthy needed to become House speaker. If you want results, you have to be part of a coalition. McCarthy actually needed a couple fewer votes because of a parliamentary maneuver in which a number of his opponents voted present.

As I learned in my interview with Marjorie Taylor Greene on Sunday, she decided to go the influence route in backing McCarthy – which pitted her against many of her friends in the conservative Freedom Caucus.

As an "anti-establishment" conservative, Greene told me, she and McCarthy said some negative things about each other, but then she "got to know him better" and they slowly developed a sense of trust.

A turning point came last summer, when she teamed up with McCarthy to foil a Democratic strategy on taxes, climate and health care. It didn’t work, but for the Georgia congresswoman and some of her allies on the right, "it was a really big deal," as she told The Hill.

Not long afterward – and I used this in our "Media Buzz" sitdown – Greene gave some revealing quotes to Robert Draper of the New York Times Magazine, who was working on his book "Weapons of Mass Delusion."

McCarthy was going to give her "a lot of power and a lot of leeway," or else the base would be "very unhappy" with him. This, she said, was not a "threat," but just "reality."

So wouldn’t it be fair, as her fellow firebrands were trying to land subcommittee chairmanships and Ways and Means slots, to say she’d already cut her deal with the incoming speaker?

"I have no promise. I have no deal," Greene said. That may be true. But surely they have some kind of understanding after she helped deliver votes for him – which, by the way, is the kind of horse-trading that has gone on since Alexander Hamilton was saying you had to be in the room.

MTG was in the room when she had Donald Trump on the line and was shocked how angrily Rep. Matt Rosedale reacted in refusing to take the call, as Greene recounted to me.

Even getting a couple of committee assignments would be an upgrade for Greene, who was stripped of hers by the Democrats after some outrageous remarks. This reflects a period when, as Greene confirmed to me, she had "easily gotten sucked into some things I’d seen on the Internet," but has since renounced the Q’Anon conspiracy theories she once believed.

MTG now views McCarthy as committed to the conservative agenda, and thinks it would be helpful for the likes of Matt Gaetz and Lauren Boebert to talk to him as well. The larger point is that she chose math over marketing, accepting that the only way to get things done is to build a coalition.

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Some of her previous fans are bashing her as a sellout for deigning to join forces with McCarthy, refusing to even listen to her for consorting with this swamp creature. There’s no way to please everyone.

When Alexandria Ocasio-Cortez was first elected, she became an Instagram superstar and joined a sit-in outside Nancy Pelosi’s office. The New Yorker has since decided that the key to accomplishing things is sometimes working with the leadership, just as all 212 House Democrats dutifully backed Hakeem Jeffries as their leader.

Now maybe this will all fall apart on the GOP side. There is sweeping media criticism that McCarthy made too many concessions to his hard-right opponents - though the media missed the mark in constantly saying McCarthy was being humiliated with each losing ballot, even predicting he’d drop out, when he was winning 95 percent of the GOP caucus and the rebels had no one who could beat him.

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Now if it turns out that Speaker McCarthy can’t pass a debt-ceiling bill or avoid a financial crisis, it may well be that he surrendered too much authority – including allowing any single member to call a snap vote to oust him. Greene and McCarthy could again find themselves at odds, though you’d think both sides now have an incentive to avoid a total meltdown.

The view from Greene-land is that most of the written commitments that McCarthy made were done early on and the extent of the concessions has been overblown. We shall see.

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Some of the grandstanding on the right "was really unnecessary and just a bunch of fanfare that helps popularity on the Internet but doesn’t produce results," Greene told me. 

There have been plenty of reasons to criticize her in the past and may well be in the future. But an eventual recognition that party lawmakers should work together to push through their agenda isn’t one of them.