Previous presidents tended to have a public-facing political strategist and confidante: George W. Bush had Karl Rove, Barack Obama had David Axelrod.

And, for a time, Steve Bannon might have filled that role for President Trump.

But with Bannon estranged from the president, Trump is entering a midterm campaign — which tends to be politically perilous for a new president — without such a nationally recognized proxy, who instinctively understands his base and has put in the time on the campaign trail with him. It’s also a Bannon-shaped void in the conservative populist movement.

“Right now it’s just the president. Steve Bannon was emerging as the guy who you could say, ‘This guy’s agenda is the president’s agenda.’ … A lot of us would be more comfortable if additional leaders would emerge, field-grade officers,” said Michael Caputo, a longtime Republican strategist and former Trump campaign aide.

Bannon had planned an ambitious anti-establishment campaign to challenge Senate Majority Leader Mitch McConnell, R-Ky., with candidates who ran on a populist, economic nationalist brand — and perhaps funded by former Bannon patron Rebekah Mercer.

However, Bannon found himself on the outs earlier this month after he was quoted in a book saying that a meeting Donald Trump Jr. and Trump son-in-law Jared Kushner had with a group of Russians during the 2016 presidential campaign was “treasonous.” They were promised incriminating information about Hillary Clinton in the meeting.

The president himself weighed in to say that Bannon, who served as White House chief strategist for the first seven months Trump was in office, had “lost his mind” and had “nothing to do with me or my presidency.” Mercer quickly put out a statement siding with the president.

“I support President Trump and the platform upon which he was elected. My family and I have not communicated with Steve Bannon in many months and have provided no financial support to his political agenda, nor do we support his recent actions and statements,” Mercer said.

Within a week, Bannon had resigned as chairman of Breitbart News, the conservative website that had served as a key bullhorn for the populist right and which Bannon once referred to as part of his arsenal of “weapons.” In October, Bloomberg reported that Bannon planned primary challengers to almost every GOP senator who was up for re-election, in a bid to weaken McConnell.

Without Bannon at the helm — and the Mercers having distanced themselves from him — much of that anti-establishment organizational energy has disintegrated.

“Without a figurehead to mobilize and organize it, where [does that movement] go? These candidates were part of the movement because they believe that they would be funded by the Mercers and aligned with Trump. That’s why they signed up,” said Kurt Bardella, the former Breitbart spokesman.

And there is a legitimate question to be asked about how successful Bannon would have been. His 2018 political effort was in its infancy, with no formal organizing to speak of at the time of his estrangement with the president.

“This is a guy who is basically leading a movement that doesn’t exist,” Josh Holmes, McConnell’s former chief of staff, told ABC News after Bannon’s preferred candidate, Roy Moore, lost the Alabama Senate election last year. “Steve Bannon is sort of the emperor who had no clothes here.”

Bannon did not respond to NPR’s request for comment.

Supporters of the president insist that Trump still has a finger on the pulse of the Breitbart wing of his base — and that he can serve as president of the United States and movement leader, all in one.

“Bannon’s self-destruction will have no impact on the Trump movement or the president’s base. No voters know who Sloppy Steve is and they don’t care,” longtime Trump confidante Roger Stone told NPR, using a moniker for Bannon that Trump created after their falling out. “It’s all inside-the-Beltway nonsense that no real people care about.”

“The president has an instinctual connection with his base. No staffer can possibly replicate that,” added Ed Brookover, a former senior Trump campaign adviser. “He understands their overwhelming desire to change how Washington [works]. His instincts are driving his agenda.”

Trump allies point to individuals like former campaign hands Dave Bossie, Corey Lewandowski and Kellyanne Conway as people who could step up to Bannon’s prior role — figures who remain in the loop, but are admittedly less antagonistic and less ideological.

Bossie, who first introduced Bannon and Trump years ago, pointed to White House aide Stephen Miller as a strong voice in the administration. Miller, who cut his teeth working for then-Sen. Jeff Sessions, was known as an immigration hardliner in the Senate.

“Stephen Miller is a tremendous leader inside the White House and out, on immigration issues going back many years — [in him] the president has someone who understands his position and is able to articulate that to Capitol Hill,” Bossie told NPR.

However, there are already signs that Bannon’s populist revolt is steadily diminishing in importance.

The same week that Bannon was ejected from Trump’s trusted circle of advisers, the White House announced that the president would be attending the annual World Economic Conference in Davos, Switzerland, a glitzy gathering of the world’s elite. Following the Republican Party’s embarrassing loss in the Alabama Senate race, the president announced he would not be supporting insurgents seeking to challenge incumbent Republican members of Congress.

“I don’t see that happening,” the president told reporters, after being asked if he would still be supporting challengers.

This week, Breitbart took the White House to task for not moving as quickly as it says they should have to secure the border.

Bannon had planned for 2018 to be a midterm season filled with a “League of Extraordinary Candidates,” a slate of conservative, economic nationalists led by Bannon and others to challenge McConnell and other Republicans in Washington, D.C.

There is little threat of that now.

“There is no narrative of McConnell in jeopardy. Once [Republicans] got tax reform done, there was nowhere to go with the ‘take McConnell out’ narrative. There is no one else driving that other than Steve Bannon,” Bardella said.

The Washington Post reported that the president even paid McConnell the ultimate Trump compliment as he managed the shutdown confrontation with Democrats.

After McConnell advised him not to reach out to Democratic leaders and instead wait for them to come to him, according to the Post, Trump told the majority leader, “You are a good negotiator.”

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