Vice President Joe Biden is spending part of his South Carolina vacation calling close friends to discuss a potential 2016 run, a longtime Democratic operative and a source close to Biden who had an extensive phone call with him this week confirmed to NBC News.

Biden is not calling people asking "if" he should run, but saying, "I am thinking about it but I’m also thinking about Beau,” according to a source close to Biden. His son Beau Biden passed away in May after a lengthy battle with brain cancer.

The source who got a call from Biden this week said, “I think he is doing the analysis and homework.”

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But added: “I can't emphasize this enough: He is distraught over Beau's passing and working through the grief.”

Aides are also "calling around" to Democratic operatives about a 2016 run. The calls were first reported by the Wall Street Journal.

The Biden confidant said before the vice president can run, he would have to get through that hurdle and he’s just not through it yet. The source says Biden is asking those closest to him what a campaign would look like if he gets through this hurdle.

This source says he strongly urged the vice president to run and believes it’s his time, arguing that Democrats are looking at the polls and are deeply worried that Clinton could be vulnerable in a general election. This source says Biden never mentioned Clinton’s email issues and those who are urging Biden to run feel as though Clinton is not exciting the base in the same way that Biden could.

Another argument Biden supporters are making in favor of a run: He will have spent 8 years in the White House which makes him the most prepared candidate. “He won’t have a learning curve,” this source and others have told Biden.

Still Biden and his supporters are aware that it is getting late. According to the Democratic operative, the campaign is likely alive and well and well planned in the minds of some of his closest supporters. There are a lot of people who have been thinking about what a campaign should look like.

Both sources say this will ultimately be a decision that Biden makes with his family. He is still on track to make a decision by late August or early September.

According to the source close to Biden: "He won't do it if he doesn’t think he can do it 110 percent."