Four GOP candidates were invited to the undercard debate Wednesday. Former Virginia governor Jim Gilmore was not one of them. (Chip Somodevilla/Getty Images)

Sixteen candidates remain in the race for the Republican presidential nomination. Fifteen of them were invited to Wednesday night’s debates.

And then there was Jim Gilmore.

“I’m very disappointed,” the former Virginia governor told me when I reached him on Wednesday. He paused, as if reflecting on his word choice. “Uh, actually, I’m angry,” he revised. In fact, “I’m really upset about this.”

Gilmore warmed quickly to this thesis.

“It’s wrong and against the public interest,” he said of debate host CNN’s decision to disallow his participation, even in the pre-debate debate of minor candidates, based on his sub-1-percent standing in the polls.

“I just am rebelling against the unfairness of it all and the wrongness of it all,” he continued. “CNN is not being faithful to the stewardship they’ve taken on.”

Gilmore would like to take up his grievance directly with CNN’s Washington bureau chief, Sam Feist, but “the guy won’t even call me back, which I consider a personal insult,” he said.

And so the former governor, Republican National Committee chairman and chairman of a national homeland-security commission did the only thing he could do: While the other candidates reached tens of millions of Americans on the airwaves, Gilmore went to his campaign office in Alexandria, Va., and tweeted out his own answers to his 1,500 followers using the hashtag #GOPDebate:

“Trump doesn’t understand the Constitution.”

“Dr. Carson waffles.”

“If Santorum becomes president he will have to obey the law to.” (sic)

From the debate stage to the media crush, go behind the scenes from the Ronald Reagan Presidential Library in Simi Valley, Calif. (Alice Li/The Washington Post)

“Fiorina ducked the question.”

“Huckabee calls for disobedience of the law.”

“Gov. Walker does not understand how wages go up.”

But as his tweets vanished into the ether with scarcely a retweet, Gilmore showed his frustration; not an hour into the rollicking, interminable debate, as the candidates on the stage finally ganged up on front-runner Donald Trump, Gilmore tweeted that it was “all process and nothing to tweet about.”

Live-tweeting the debate from which he was excluded was but one of many indignities Gilmore had endured of late.

For one, he seems to be doing his own staff work. He has been known to send reporters e-mails from his Gmail address, providing his cellphone number and asking them to call. I used the number to call him Wednesday, and he was grateful for the attention: “It’s like water in a desert to me.”

I attempted to serve as an oasis for the parched candidate. Could he say how much money he has raised?

“Nope, can’t do that,” he answered. (He has not yet had to file a report to the Federal Election Commission.)

Would he run ads?

“We’ll augment our strategy with ads if we raise enough money to run ads,” he replied.

How about campaign staff?

“Okay, let me count,” he replied. “Dan. Dick. . . . Alex. Um, let’s see here. Um, Jeff. . . . I think seven at this point,” although “some are part time.”

Gilmore is aggrieved by my Post colleague David Fahrenthold, who wrote that Gilmore “has not held a single formal campaign event with actual voters present.”

The governor finds this to be “a little cute” because he actually does go to campaign events — just not his own. “I don’t need to” have campaign events, he said, because there are plenty of committee meetings and candidate forums he can attend. In fact, he has visited New Hampshire nine times this year, he said.

But with little to show for it. CNN said Gilmore was the only candidate who had been in either of last month’s Fox News debates who didn’t meet its requirement of averaging 1 percent support in any three polls released over a two-month period.

“They’re being inflexible with me!” he protested, and he had a point that his exclusion — even from the undercard debate — seemed gratuitous.

George Pataki and Lindsey Graham made the JV event even though they averaged 0.5 percent in recent polls, and CNN bent its requirements to allow businesswoman Carly Fiorina to join the main event Wednesday night.

“And yet they turn around and draw a strong line on me?” Gilmore said.

But none of this changes the governor’s strategy: to “finish as high as possible” in New Hampshire, then ride his momentum into South Carolina. How high? “I’m not going to make a prediction.”

In theory, there should be room for a “common-sense conservative” such as Gilmore on the debate stage and in the race. He thinks Trump and others are too harsh on immigration, Graham is too hawkish and Jeb Bush is wrong on education. He believes John Kasich is wrong on entitlements and Ben Carson is wrong on veterans.

“I am a grown-up in the room,” he told me.

Maybe that’s his problem.

But the governor isn’t bowed. “I ain’t gettin’ out — period,” Gilmore said.

Not getting out — yet not being let in.

Twitter: @Milbank

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