Many conservatives, such as Fox News host Sean Hannity, have been pushing for the Gingrich pick for a long while, pointing to his strong experience, debate skills, and political acumen.
The Fox News host flew the former House speaker to Indianapolis early Wednesday morning to meet with the Republican nominee as he holds late-stage meetings with his VP finalists, the sources said.
Gingrich served as a paid Fox News contributor until Tuesday night, when the network suspended ties with him "due to the intense media speculation" about his "potential selection as Donald Trump's vice presidential candidate".
The comments come after Gingrich openly wondered whether his freewheeling style - and Trump's - would make them a good ticket.
Gingrich is still paying off the debt from his 2012 presidential campaign, which stood at $5 million as of May.
Gingrich's remarks, captured on a previously undisclosed recording of the speech reviewed by ProPublica, mixed admiration for Trump's success in the primaries and skepticism about whether he could prevail in a general election.
In an address on Facebook Live, the ex-Georgia lawmaker said "all sorts of rumors are swirling" about Trump's race and that he was flattered to be in the running, adding that he and Pence were the top two final contenders. "How we make the transition from, you know, language for fourth graders to real policy", Gingrich rhetorically asked, saying, "I don't know". What's more, according to what Gingrich told the Republican State Leadership Committee during their meeting in Washington, D.C., it seems he was praising and insulting the NY real-estate mogul. I've taken on the establishment of both parties, I've been very prepared to fight in the media. He later said he still hasn't heard from Trump, but thinks that will happen this afternoon.
Left largely unmentioned: New Jersey Gov. Chris Christie, who also spoke to Trump about the vice presidency via phone on Wednesday, and Sen. Jeff Sessions (R-Ala.) remaining possibilities. Gingrich said he believed that they were largely out of the running.