But as president, Trump's campaign machine has dramatically escalated, powered by a historically large war chest of donations large and small that has given him a head start over the eventual Democratic nominee.
At this point in the last election, Trump's campaign employed 19 consultants. Now, there are more than 200. When Trump had all but locked up the nomination by May 2016, he had spent $63 million. Thus far, pro-Trump committees have spent $531 million.
Part of that money has been used to try to influence the Democratic primary. The committees recently launched a $10 million ad offense targeting Democrats, particularly former vice president Joe Biden, in early primary states.
The spending has also created a financial boon for a political-consulting class he once shunned.
Since 2017, nearly $92 million has flowed to dozens of firms providing political consulting services to Trump's 2020 reelection machine, according to an analysis of campaign spending by The Washington Post.
Beneficiaries of that money include a mix of experienced hands who have long been part of the GOP establishment and a newer crop of strategists who rode Trump's coattails to a potentially lucrative career in presidential politics.
The hiring of these consultants marks a major shift from 2016, when Trump's upstart campaign won the GOP nomination on a shoestring budget and without a robust staff to carry out basic campaign functions, like polling, door-knocking and advertising.
Trump's team in 2016 was "building the airplane while it was in flight. To their everlasting credit, they landed that airplane," Trump campaign spokesman Tim Murtaugh said. "Last time, it was insurgency. And this time, there is a feeling of insurgency - but the candidate, after all, is the president of the United States."
Trump touted his lean operation as a testament to his business savvy, comparing it favorably to his opponents, who were armed with expensive campaign consultants: "The consultants and the fundraisers and all of these people, they take the money. ... Better than being a real estate broker, to be honest with you," Trump, a real estate developer, joked in 2015.
Now, Trump has a roaring reelection apparatus. There are six main committees working to secure his second term, including the official campaign, the Republican National Committee and a super PAC. Together, they have already raised over $736 million - more than any previous presidential candidate at this point in the campaign.
Nearly $92 million of that money has flowed to 76 vendors that provide political consulting, each one drawing at least $50,000 from these committees since 2017, according to a Post analysis of federal campaign filings.
Some of those pulling in the most are run by well-known Trump loyalists, including campaign manager Brad Parscale, former campaign manager Corey Lewandowski, longtime bodyguard Keith Schiller, and former White House spokesmen Sean Spicer and Raj Shah.
Others are longtime GOP firms that worked for his 2016 opponents. Top recipients of Trump reelection spending include McIntosh Co., formerly a fundraising consultant for the super PAC supporting former Florida governor Jeb Bush, and Pluvious Group, formerly a fundraising consultant for Sen. Marco Rubio, R-Fla. Representatives for these companies did not respond to requests for comment.
These payments, reported in federal filings, do not indicate whether individuals running or managing the companies are personally profiting. In many cases, payments are passed on to other vendors or pay for staff salaries.
The spending shows how much Trump is benefiting from the decision, different from his predecessors, to begin fundraising for his second term as soon as he was elected. He has been as successful at raising money from his loyal base giving $20 at a time as he has with wealthy donors giving six figures.
The expenditures also illustrate how dramatically Trump's operation has evolved since mounting his unorthodox campaign for the White House four years ago.
When he was the underdog, Trump criticized the Republican establishment as sharply as he attacked Democrats. He even accused leaders of his own party of trying to undermine him.
"I'm not part of the corrupt system. In fact, the corrupt system is trying to stop me," Trump said in August 2016. "The voters in the Republican Party this year defied the donors, the consultants, the power brokers and chose a nominee from outside our failed and corrupt broken system. The nominee is me."
But Trump's 2020 campaign committee and the party are working in lockstep.
No one embodies this transformation more than Parscale, a Web developer from San Antonio with no previous political experience. He was tapped from obscurity to build the 2015 website for Trump's presidential exploratory committee. He has said he did the initial task for a fee of $1,500.
Parscale is now the Trump 2020 campaign manager. Three businesses associated with Parscale have received a combined $38 million since 2017 from five committees working to reelect Trump, including the Republican National Committee.
Parscale declined to be interviewed for this story. The bulk of the payments to Parscale's company, Parscale Strategy, is used for salaries and overhead, campaign officials said. The campaign set up a company, American Made Media Consultants, to place all ads for the reelection and to separate Parscale's personal interests from the campaign's advertising, officials said.
Lewandowski's firm, Green Monster Consulting, received more than $200,000 since 2017 by two of the committees supporting Trump's reelection: the America First Action super PAC and the Great America Committee, which is Vice President Mike Pence's leadership PAC.
Lewandowski said his firm is no longer paid by the super PAC and declined to answer additional questions about his work. From June 2018 through July, Lewandowski's firm received $10,000 per month from the Great America Committee.
Both men are now prominent party figures in Washington, working alongside the establishment.
Parscale speaks regularly with Karl Rove about campaign fundraising, according to someone familiar with their conversations who spoke on the condition of anonymity. Rove, one of the most influential architects of the modern GOP political fundraising machine, was publicly critical of Trump in 2016.
Lewandowski, now a regular television commentator amplifying Trump's message, is a Washington lobbyist considering a run for a U.S. Senate seat in New Hampshire.
Shah declined to comment. Schiller's attorney did not respond to a request for comment. Spicer said his company is being paid for his work as a senior adviser and spokesman to the America First Action super PAC, and he helps with fundraising and publicity for the group.
Asked whether the slew of political consultants has diminished the outsider appeal of Trump's candidacy, Murtaugh said: "Donald Trump is who he is, and nothing will ever change." Murtaugh noted the campaign is a massive enterprise that has already raised and spent hundreds of millions of dollars and "requires a lot of people to help."
Some consultants have played a crucial role in helping direct donors' money to the right recipient - a reflection of the sophisticated and organized fundraising and spending efforts that exist behind the scenes.
A key example is the role of longtime Pence aide Marty Obst and the work of his firm, MO Strategies, that has received more than $660,000 since 2017 from four of the six committees.
Obst was a part of the team that launched the main pro-Trump super PAC, America First Action. After he left the group, his company provided consulting services for the Republican National Committee and an affiliated fundraising committee. He runs the Pence leadership PAC and is an unpaid strategist for the Trump campaign.
Obst declined to comment for this story.
Trump is armed with a bigger reelection operation than his predecessors had at this stage in their campaigns.
By this point in 2011, the official committees working toward President Barack Obama's second term had raised at least $390 million - a little over half of what Trump has now, campaign filings show.
During the 2016 campaign, one way Trump saved money was by leveraging his celebrity, bombast and larger-than-life personality to attract coverage in the media.
"He was on TV all the time," said Alex Conant, GOP strategist and senior adviser to Rubio's 2016 campaign. It "turned out to be a brilliant strategy, and one that doesn't require much campaign infrastructure - just a cellphone and proximity to a TV camera."
Trump still enjoys those advantages. But he now has internal polling, a system to test messages on Facebook to figure out what ads resonate most with voters and a rapid-response team tasked with mounting a public relations offensive at a moment's notice.
"It's night and day," Spicer said. "Before, it was like a forced arranged marriage between the RNC and the campaign. But now, by launching so early, you can think strategically about what services they need, when they need them, when they need to bring in-house or an outside person."
Trump's campaigning head start comes on top of the unique perks enjoyed by sitting presidents over their challengers, such as having the support of multiple official committees that work in tandem for the party's nominee.
Already, more than two dozen of the top-earning consultants are doing consulting work for multiple committees, highlighting how the sprawling operation relies on a core group of players. It also raises questions about how the groups are following rules barring coordination.
Kelly Sadler, a spokeswoman for the America First Action super PAC, said the group strictly adheres to all federal election rules and regulations prohibiting coordination between vendors.
America First Action said many of the vendors that worked for the super PAC and the party committee no longer are paid by the super PAC.
"We have hired political professionals, both in-house and externally, who have worked in this field for years and take these obligations seriously," Sadler said.
RNC officials said that as a part of their contracting process, they require evidence from potential vendors that they have established the necessary firewalls.
Among other top firms paid for political consulting by the party or the super PAC are a handful of limited-liability companies with little public presence or paper trails, obscuring the names of those who are running these businesses.
Two of those companies were St. James Strategies and Red Strategy Group, which shared an address with another Republican National Committee vendor, Red Wave Strategies. All three are housed at the Virginia law offices of Holtzman Vogel Josefiak Torchinsky.
The law firm said it does not comment on its clients.
The six Trump committees in The Post's analysis are Trump's reelection campaign, the Republican National Committee, the two affiliated fundraising committees, the official pro-Trump super PAC America First Action and the Great America Committee, which is Pence's leadership committee.
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