Broidy allegedly helped broker meetings between Nader and Trump, and also had a profitable business relationship with the UAE.
According to the Wall Street Journal, which broke the story, and The New York Times, the $1.6 million payment to the woman was brokered by attorney Michael Cohen - President Donald Trump's personal lawyer whose offices were raided by the Federal Bureau of Investigation on Monday.
In a statement on Friday, Mr Broidy acknowledged that he had a relationship with a Playboy Playmate and offered to help her financially after she told him she was pregnant.
'At the end of our relationship, this woman shared with me that she was pregnant. "She alone decided that she did not want to continue with the pregnancy and I offered to help her financially during this hard period", Broidy said in a statement provided to the AP.
Broidy apologized to his family in his statement: "It is unfortunate that this personal matter between two consenting adults is the subject of national discussion just because of Michael Cohen's involvement".
An attorney for Cohen did not return requests for comment Friday. Broidy's financial support came alongside access to Trump, helping him regain political status after his 2009 plea deal admitting to making illegal gifts to New York State officials.
Broidy said Cohen reached out to him after being contacted by the woman's attorney, Keith Davidson.
The payout was similar to a $130,000 payout that Cohen organized for Stormy Daniels, an adult film actress who claims to have had sex with Trump, immediately prior to the 2016 presidential election.
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The 30-year-old has a pending lawsuit alleging collusion by the league office, owners and teams to keep him out of the NFL . At the upcoming league meetings in May, Mortensen said the anthem issue is "back on the front burner".
A source familiar with the situation said Republican National Committee chairwoman Ronna Romney McDaniel has accepted Mr Broidy's resignation.
Federal prosecutors are investigating Cohen for possible bank fraud and campaign finance violations in connection to his efforts to tamp down damaging stories about Trump during the 2016 campaign, according to people familiar with the case.
The matter might have remained personal, as the relations between a California businessman and a Playmate is nothing unusual in Tinseltown, but Broidy reportedly helped raise over $108 million in funding for Trump's 2016 presidential campaign and donated more than $160,000 to the RNC a year ago.
Mr. Broidy was a major fund-raiser for George W. Bush, but he is particularly connected in Mr. Trump's orbit. "I'm gonna take a look", she said. "We have not spoken since that time".
Cohen and Trump are now being sued by porn star Stormy Daniels, who seeks to void her own hush deal over an alleged dalliance with Trump for which she was paid $130,000. President Donald Trump's personal lawyer, Michael Cohen, arranged the 2017 deal. Daniels has sued Cohen and Trump, claiming the contract is invalid.
Cohen used the same pseudonyms in a non-disclosure agreement between Broidy and the Playmate that he used in a similar agreement that involved Trump and Daniels, whose real name is Stephanie Clifford.
Davidson and Cohen were also in communication about a third agreement involving former Playboy centerfold Karen McDougal. She has said she understood that American Media Inc. was buying her story not to publish it, but to bury it, in what has been called a "catch and kill" arrangement.
Trump has denied the women's allegations.