Christie has received the official paperwork for the process, an unnamed source also told CNN.
From "manservant" to right-hand man, the governor has rapidly ascended the internal ranks of the Trump campaign.
Shortly after ending his own primary bid, Christie became one of the first elected Republican officials to endorse Trump and has since become one of his highest-profile surrogates. In May, Trump announced that Christie would serve as the chairman of his transition team if he won the White House, calling him "extremely knowledgeable and loyal."
Besides name-dropping former House Speaker Newt Gingrich—who Trump said he was "absolutely" considering in an interview with "Fox & Friends"—Trump has revealed very little about his vice presidential short list so far.
"Keep a little suspense at least, right?" the candidate joked to Fox News' "On The Record."
h/t The Hill