Washington (CNN) President Donald Trump says he's returning a favor by recording a campaign robocall in the Senate Pennsylvania primary for one of his earliest supporters in the 2016 presidential campaign.

"Tuesday is Election Day, and I need you to go out and vote for my good friend, Lou Barletta, a very special guy," Trump says in the recorded call set to be released on Monday.

In the two-minute call, Trump points to Barletta's early backing of him in the 2016 presidential race. Trump narrowly won Pennsylvania in the contest.

"He was with me early on before everyone else started jumping on board, Trump says in the call. "It took courage for Lou to do that, and I'll never forget it. That's why I'm standing with Lou Barletta now."

Trump highlights Barletta's conservative immigration positions and his support for the GOP tax overhaul that passed in December.

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