Lewandowski: VP List is Very Small

Corey Lewandowski, one of Donald Trump's closest aides, says the presumptive Republican presidential nominee's campaign is closing in on a running mate.

"I can say that the list is very small, and we have a very good understanding of who those individuals will be and the decision will be made by Mr. Trump," Lewandowski said on "Fox News Sunday.

Lewandowski is in charge of vetting potential vice presidential candidates. But he's not naming who the major contenders are.

Among the names that have been leaked: New Jersey Gov. Chris Christie, former Speaker Newt Gingrich, Rep. Marsha Blackburn, and South Carolina Gov. Nikki Haley.

Earlier this month, Trump said he would stick with tradition and name his running mate at the Republican National Convention in July.