Trump was speaking at a televised campaign event in South Carolina on Tuesday when he turned his attention to the state's senior senator (and fellow Republican presidential hopeful) Lindsey Graham.
"I got called a jackass by this guy," Trump said, referring to a comment Graham made to CNN earlier in the day in response to Trump's assertion that Senator John McCain is "not a war hero."
"Then I said to myself, 'Hey, didn't this guy call me like, four years ago?' Yes," Trump continued. "Lindsey Graham, I didn't even know who he was."
The businessman and host of the reality TV show Celebrity Apprentice explained that Graham had called him looking for a "good reference" on the Fox News program Fox & Friends, on which Trump is a regular guest, and also to solicit campaign donations.
Trump said he agreed to mention the "begging" senator's name on television, at which point Graham gave him his contact information.
"He gave me his number and I found the card," Trump told the crowd, holding up a piece of yellow paper. "I don't know if it's the right number, let's try it ..."
After reading out the phone number twice, he encouraged audience members to "give it a shot."
"Your local politician, you know?" said Trump. "He won't fix anything, but at least he'll talk to you."
And yet, as Graham is surely learning, Trump's message was heard far beyond the few hundred people gathered in South Carolina.
Anyone who was watching the speech on television, or as it was streamed live online, or afterwards when it was uploaded to YouTube is now privy to what has been confirmed by Graham's spokesperson as the senator's private cellphone number.
Essentially, Graham has been doxxed — a term that refers to the act of publishing someone's personal information online against their wishes, most often used in the context of internet trolls.
Many on Twitter have admitted to calling Graham using the number Trump gave out, though aside from one Politico reporter who (presumably) called before the phone lines got tied up, nobody has reported being able to reach the politician directly.
"I wonder what caused that," Graham told Politico. "When it comes to the Donald, nothing surprises me anymore."
CBC News was greeted with a recorded voicemail message upon calling the number, like many other media outlets attempting to confirm its veracity. The recording can be heard here:
Graham's campaign manager Christian Ferry sent the following statement to Bloomberg via email in response to Trump's actions.
"Donald Trump continues to show hourly that he is ill-prepared to be commander in chief. The two people most excited about Donald Trump's candidacy are Barack Obama and Hillary Clinton. Because of Trump's bombastic and ridiculous campaign, we aren't talking about Obama's horrible deal with Iran or Hillary Clinton's plans to continue Obama's failed national security agenda."
Graham himself joked about the situation on Twitter approximately three hours after his phone number was leaked, writing "Probably getting a new phone. iPhone or Android?"