WASHINGTON (AFP) - Donald Trump named a former Goldman Sachs partner as his new finance chairman on Thursday, as the presumptive Republican nominee seeks to raise US$1 billion (S$1.3 billion) for his November showdown with likely Democratic standardbearer Hillary Clinton.
Steven Mnuchin, chairman and chief executive of private investment firm Dune Capital Management, "brings unprecedented experience and expertise to a fund-raising operation that will benefit the Republican Party and ultimately defeat Hillary Clinton," Trump said in a statement.
The campaign said Mnuchin has previously worked with Trump "in a business capacity."
Trump boasted during much of the primary race that he was self-funding his campaign, and has pumped nearly US$40 million into his presidential bid.
Now that his Republican rivals have dropped out of the race and he has emerged as the all-but-certain nominee, he acknowledged he will need to raise money on a completely different scale for the general election.
"We're going to try and raise over a billion dollars, which is what's going to be necessary," Trump said on Wednesday in an interview with NBC Nightly News.
"I hear the Democrats maybe will get as high as US$2 billion," he said.
Mnuchin said he aims to "create a world class finance organisation to support the campaign in the general election."
Like Trump himself, Mnuchin has a history of contributing to a mix of Democrats and Republicans.
During the 2000 presidential election, Mnuchin donated to Democrat Al Gore and Republican Steve Forbes, while in 2004 he donated to Democrats John Kerry and John Edwards.according to the Centre for Public Integrity.
Four years later, he contributed to several campaigns including those of Democrats Barack Obama, Clinton, and Bill Richardson, and Republicans Rudy Giuliani and Mitt Romney, while in 2012 he donated to Romney and fellow Republican Tim Pawlenty, according to CPI.
Mnuchin was a longtime partner at Goldman Sachs, a giant Wall Street firm that Trump has criticized on the campaign trail.
In January, after it was revealed that Trump's then-rival Ted Cruz took a low-interest million-dollar loan from the bank, Trump sneered that "Goldman Sachs owns him."
Cruz's wife Heidi Cruz is an executive at the investment bank.
Trump has been steadily beefing up his campaign in recent weeks, after operating for months with scaled down ground operations in several states despite outperforming other candidates.
In April, he brought on seasoned operative Paul Manafort and political veteran Rick Wiley and has said he will now expand his campaign dramatically.
"I have a terrific staff and now obviously we have to build it up, because we'll be going all over the country," Trump said on Wednesday.