Donald Trump's campaign is turning toward the general election, and away from loyal campaign manager Corey Lewandowski.

In a statement Monday, Trump's spokesperson Hope Hicks said Lewandowski will "no longer be working with the campaign."

"The campaign is grateful to Corey for his hard work and dedication and we wish him the best in the future," Hicks said in the statement.

It's a big shift from the primaries for the presumptive Republican nominee.

Tensions have mounted in the Trump campaign since the candidate secured the number of delegates to become the presumptive nominee. Trump brought on Paul Manafort as his chief strategist in the middle of the primaries. Manafort has reportedly had a strained relationship with Lewandowski – when Manafort was brought on it was unclear who was really calling the shots on the campaign. Eventually, Manafort was given the role of chair the campaign after privately telling Republican leaders Trump would be more "presidential" as the official nominee.

Now that Hillary Clinton has also secured her delegates, the general election is underway, Trump has decided to side with Manafort to get him across the finish line.

Who was Trump's campaign manager?

Months ago, it seemed Lewandowski would be in the race until the end. After a big win in the Florida primaries, Trump took the stage in Palm Beach surrounded by what he called his "squad"; to his right stood the then lesser-known Lewandowski.

Trump was loyal to Lewandowski, even after a reporter alleged that Lewandowski physically assaulted her at a Trump campaign rallyin Florida.

Before Trump, Lewandowski had led a rather banal political career as far as Republican operatives go.

In the past, Lewandowski, 41, has worked for the Republican National Committee, assisted former Ohio Rep. Bob Ney (the man who mandated french fries be renamed "freedom fries" on congressional food service menus), and headed a failed US Senate reelection campaign for Robert Smith (the man who stabbed a plastic doll on the Senate floor to take a stand against abortion).

For nearly seven years he worked for Americans for Prosperity, a group sponsored by key conservative figures Charles G. and David H. Koch, where he served as a regional director and managed their voter registration program, which came under investigation in 2014 for sending out misleading mailers to voters.

Lewandowski maintains he left AFP on his own accord, but according to reporting from Politico, it became clear that his involvement with the voter registration mess helped nudge him toward the exit.

But in June 2015, Lewandowski officially went to the Trump campaign — making a hard turn toward the anti-establishment strain of the party.

Even so, the man who brought Trump and Lewandowski together, Citizens United president David Bossie, told the New York Times that Lewandowski "is as antiestablishment as Mr. Trump."

Lewandowski has a reputation for being tough

In the past months, multiple news outlets have taken a stab at uncovering the true Lewandowski, who, according to former colleagues, is known for his aggressive and quick temper.

The Wall Street Journal captured this essence in an introduction to a profile of him:

In a stairwell behind the stage as Republican presidential candidate Donald Trump spoke at a packed rally recently, campaign manager Corey R. Lewandowski lashed out at his New Hampshire state director. "My boss is working 20-hour days; you’re not," Mr. Lewandowski said. "You’re not meeting any of your metrics with the primary three weeks away." In the motorcade afterward, Mr. Lewandowski called a longtime aide supervising another state: "Fly here tonight and take over."

Politico found that Lewandowski has long been accused of bullying, including once calling a female colleague at AFP the c-word in front of other employees. Trump's decision to bow out of the Conservative Political Action Conference followed a "profanity-laced tirade" from Lewandowski when organizers insisted Trump's speech must be accompanied by a Q&A session, and Fox News called out Lewandowski for threatening Megyn Kelly during Trump's months-long feud with the debate moderator.

In any other primary election cycle, Lewandowski's actions would have likely already cost him his job. (Remember, Ted Cruz fired his top spokesperson for spreading a false story about Marco Rubio in late February.)

Rubio commented on the incident with Fields, the Breitbart reporter, on conservative radio host Mike Gallagher's show, calling it a campaign-ending incident.

"If my campaign manager had done that, my campaign would be over," Rubio said. "He would have had to resign, and my campaign may be over. I would have had to quit that very day."

But not Trump.

Lewandowski let Trump be Trump

From the start of the campaign it has become clear that being Trump works best for Trump, and that is how Lewandowski operated.

"Let Trump be Trump" was written on his office whiteboard since the start of the presidential bid, according to the Wall Street Journal.

Trump writes (or doesn't write) his own speeches, and has made a show of speaking what is on his mind. On the Trump campaign trail, Lewandowski let this strategy play out. He went on TV to clarify Trump's statements, but for the most part, like Trump's campaign spokesperson Hope Hicks, he and his team stand back.

Now, no longer by Trump's side, Lewandowski’s most important public move will probably come this summer at the Republican National Convention, where he remains one of the 11 delegates for New Hampshire, according to a list the Trump campaign turned over to the New York Times on February 26.

He will no longer be playing double duty at the convention, he will just be voting for his candidate.

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