The person confirming the move did so on condition of anonymity. Trump's campaign and Fabrizio did not immediately comment. News of Fabrizio's hire was first reported by Politico.
While Trump often boasts about his public poll numbers, he opted for months to operate without his own pollster — setting him apart from top rivals who invested heavily in the ability to conduct customized surveys to learn about voter attitudes on various issues and across a broad spectrum of geographic areas.
Fabrizio has worked for numerous top Republicans, including Florida Gov. Rick Scott and Senate Majority Leader Mitch McConnell (R-Ky.). He polled for Kentucky Sen. Rand Paul's presidential campaign.
In an interview with NBC's "Meet The Press" last August, Trump said: "I don't have pollsters. I don't want to waste money on pollsters. I don't want to be unreal. I want to be me. I have to be me."
On Monday night, some Trump foes resurfaced some old tweets from when Fabrizio was Paul's pollster and he appeared to endorse or level criticism at Trump:
But more recently, Fabrizio has encouraged the mogul on social media, sometimes retweeting him.