Donald Trump has elevated "the most dangerous political operative in America" to a senior role in his campaign, a move that could mean an even more nationalistic and populist tenor to his election bid. 

The Republican presidential nominee Wednesday morning announced he has appointed Breitbart News executive chairman Stephen Bannon chief executive of his campaign. A Bloomberg profile last year described him as "the most dangerous political operative in America." Paul Manafort will remain campaign chairman and chief strategist.

Bannon has been urging the candidate for months to run more fully as an outsider and nationalist, reports the Washington Post, and to spurn the advice of those telling him to tone it down. 

A former naval officer and investment banker at Goldman Sachs (GS) - Get Report , Bannon is known for his fiercely anti-establishment attitude. He embraced Sarah Palin and populism early on, and his Breitbart helped to drive out former Speaker of the House John Boehner. He is the host of the Breitbart News Daily Show on Sirius XM  (SIRI) - Get Report radio and has dabbled in film, producing 2004's "The Face of Evil: Reagan's War in Word and Deed" and 2016's "Clinton Cash," among others.

Bannon is also the co-founder and executive chairman of the Government Accountability Institute, a nonprofit investigative research institute that dives deep into the lives and dealings of major politicians. It has delved into the finances of both Democrat Hillary Clinton and Republican Jeb Bush, with the group's president, Peter Schweizer, authoring titles on both. GAI often partners with major media outlets to disseminate the information it uncovers.

"What Peter and I noticed is that it's facts, not rumors, that resonate with the best investigative reporters," Bannon told Bloomberg.

Could Bannon's hire and the promotion of campaign strategist Kellyanne Conway to campaign manager (announced along with the Bannon move) will breathe some fire into his presidential bid? It has hit a rocky patch in recentweeks. Trump trails Clinton by more than 6% nationally, according to a RealClearPolitics average of polls, and is losing to her by a wide margin in key battleground states like Pennsylvania and Virginia. Trump's relationship with campaign chairman Manafort has also become increasingly strained, and Manafort's role in the campaign is reportedly diminished.

RCP Current Poll Average - Clinton vs. Trump vs. Johnson | InsideGov

"I want to win," Trump told the Wall Street Journal, which first revealed the campaign hires. "That's why I'm bringing on fantastic people who know how to win and love to win."

A coordinator for the Trump campaign speaking with TheStreet on the condition of anonymity said he sees the maneuver as strategic, specifically in relation to the press (with which Trump has struggled). "Manafort was brought on board to corral the GOP establishment, and I think he did a good job of it. With Bannon and Conway, we're seeing a shift in priorities towards media coverage," he said.

A former senior Trump staffer said he didn't see the new hires as unusual or particularly bad for the team currently in place. "Historically, presidential campaigns expand senior leadership in the run up to Labor day. Kellyanne is a longtime friend and adviser to Mr. Trump and is merely adopting the right title. ... [Bannon] is brilliant and he'll be helpful in a filled out leadership," he said.

But, the move could backfire. There is talk of Bannon's appointment signalling the draw down of mainstream GOP support for Trump's bid. 

And Rick Tyler, former campaign spokesman for Ted Cruz, acknowledged on MSNBC's "Morning Joe" Wednesday that the Bannon hire may be a bit controversial. "You probably hear from a lot of people who have worked with Bannon that he's not the easiest person to get along with. He has a very volatile temper," he said.