WASHINGTON (NYTIMES) - Early in his presidential campaign, Mr Donald Trump dismissed political data as an "overrated" tool.
But after he won the Republican nomination, his team began building a database that offers a pipeline into the heart of the party's base, a comprehensive list including the e-mail addresses and cellphone numbers of as many as 20 million supporters.
Now, consultants close to the Trump campaign are ramping up efforts to put that database - by far the most sought-after in Republican politics - to use, offering it for rent to candidates, conservative groups and even businesses.
It is an arrangement that has the potential to help the Republican Party in key midterm races, while providing a source of revenue for Mr Trump's campaign and the consultants involved.
It has also set off concerns about diluting the power of one of Mr Trump's most potent political assets, while raising questions about whether his team is facilitating the sort of political profiteering that he disparaged during his campaign.
It is not unusual for candidates to rent supporter data to - or from - other campaigns. The new effort by Mr Trump's team, however, appears to be the first time the campaign of a sitting president facing re-election has opted to market its list.
Federal election law allows campaigns and political action committees to sell or rent their lists, provided that the payments received are fair market value.
In recent weeks, Mr Trump's campaign, which is not known for its adherence to political norms, quietly signed a contract with a newly formed Virginia-based company called Excelsior Strategies to market the e-mails and mobile phone numbers - what is known in the political industry as first-party data.
Excelsior is offering the chance to e-mail Mr Trump's supporters at a rate of US$35 (S$48) per 1,000 addresses - or more if the renter also wants to push posts into the Facebook timelines of supporters - according to interviews and marketing e-mails obtained by The New York Times.
The firm has also explored the possibility of clients' being able to send text messages directly to the phones of Mr Trump's supporters, according to the marketing e-mails and interviews.
Those contacts could be of tremendous benefit to Republican candidates or political groups around the country seeking to capitalise on their base's enthusiasm for the President.
"Republicans have suffered from being behind in small-dollar fundraising, and the President, over the course of the campaign and his presidency, has built the largest Republican first-party data list," said Mr Trump's campaign manager Brad Parscale, who engineered the agreement.
"So giving other candidates and groups access to that data through a legal means to rent it was one of the best things I could do for the Republican ecosystem. And the campaign makes a little money, too. It's a win-win."
So far, parts of the list have been rented to a number of Republican candidates - including the gubernatorial campaign of Mr Ron DeSantis in Florida and the Senate campaign of Mr Josh Hawley in Missouri - as well as non-profit groups advocating the confirmation of Judge Brett Kavanaugh to the Supreme Court, and even to an author promoting a pro-Trump book, according to people familiar with the arrangement.
Digital files of supporters' data have become indispensable tools of modern campaigns, relied upon for fund raising, mobilising volunteers and rallying supporters to get out to vote.
And they have become valuable currency in their own right, sometimes reaping millions of dollars in rental fees for the campaigns that built the lists and the list brokers who arrange the rentals.
It is not uncommon for former candidates to rent or sell their lists to pay down debts, or for active campaigns to swap parts of their lists with those of ideologically aligned party or campaign committees to build their networks.
The Trump campaign maintains ownership of the list as well as veto authority over all rentals, according to interviews and the marketing e-mails.
One such e-mail indicates that "as long as the political group, org, nonprofit or business is not hostile to the president, then they are most likely able to use the data with no problem".
It is not clear whether the President, who is known to abhor the prospect of others' profiting from their affiliations with him, is aware of the details of the arrangement.
The people familiar with the arrangement said that the rentals so far have been sparing, but that the volume began increasing in recent weeks as key midterm races began heating up.
They said that roughly 85 per cent of the funds paid for the rentals will be passed through to the Trump campaign.
Excelsior will keep whatever portion of the remaining 15 per cent is left after it pays its overhead and subcontractors, including an e-mail fund-raising company called Campaign Inbox that was started after the election by people who worked on Mr Trump's campaign, including Mr Matt Oczkowski, a former official at the defunct data outfit Cambridge Analytica.
It is unclear how much the arrangement has yielded for Excelsior, Campaign Inbox or the Trump campaign to date.
That is partly because such transactions may not be completely traceable through campaign finance filings and partly because the filings on record mostly only cover expenditures through the end of June - before the arrangement was completed.
The arrangement replaces an earlier one that had relied on companies owned by Mr Parscale, a close confidant of the Trump family who had played a key role in building the list as the digital director of Mr Trump's 2016 campaign.
During that campaign, his company, Giles-Parscale, was by far the biggest vendor, receiving nearly US$88 million in payments, though most of the money was probably passed through to Facebook and other platforms for ads.
In the months after Mr Trump's election, another company owned by Mr Parscale began quietly renting out the list to a few campaigns, though people who work with the Trump campaign said that he did little to solicit such rentals.
Federal Election Commission filings show that from the beginning of 2017 to the end of this June, Mr Parscale Strategy paid Mr Trump's campaign more than US$236,000 in "list rental revenue".
But when Mr Parscale was tapped to be Mr Trump's re-election campaign manager in late February, he began exploring other ways to manage and expand list rentals.
He feared he would not have the time to oversee the process, and also wanted to avoid the perception that he was enriching himself from the campaign, the people who work with the campaign said.
He approached Mr Mike Shields, a veteran political consultant who had helped found his own company, Convergence Media, after the election. Mr Shields recommended a top executive at Convergence, Mr Tom Newhouse, who had worked at the National Republican Congressional Committee.
Excelsior was incorporated in March, according to Virginia state records. People familiar with the company say that Mr Newhouse controls it, but that the company shares employees with Convergence Media.
One employee of Excelsior and Convergence wrote to Republican consultants last month that "Convergence Media recently started a partnership with the Trump campaign to be the exclusive broker of all of their campaign data, including their donor data".
The data, the employee said, "is currently available to be used for e-mail and Facebook advertising", adding that text messaging and online advertising should be available soon.
Within the new initiative, there has been some confusion about the precise roles and relationships of the companies involved.
Mr Rob Simms, who helped found Convergence with Mr Shields said, "Convergence Media is not a vendor to the Donald J. Trump for President campaign."
Mr Parscale praised both the Convergence team and Mr Newhouse as responsible stewards of the Trump campaign's data.
"This first-party data is very sensitive and valuable, and you don't want to have a lot of people in it," he said. "Tom has an outstanding reputation, and I trust him. There are a lot of bad actors in town and I don't think he is one of them."
While list brokers could not recall any previous first-term presidents renting their lists through vendors, Mr Trump is the first such president since a 2014 Supreme Court ruling made the campaign finance legal landscape more amenable to such list-sharing. It struck down a law that had prevented donors from giving big checks to as many candidates as they wanted.
Still, there are practical reasons to avoid widespread rentals of the Trump campaign list, warned Mr Cyrus Krohn, who helped build the Republican National Committee's list into a digital force as the committee's digital director during the 2008 election cycle.
"We've already become so inundated with an influx of political messaging that I would be concerned about oversaturating supporters with e-mails," said Mr Krohn, who left Washington and now runs a technology startup in Seattle. "The response rates are going to degrade and the performance is going to wane."