The latest on the veepstakes, Sanders to endorse Clinton

Trump-Gingrich? Clinton-Kaine? Clinton-Warren? Trump-Christie? The political soothsayers are looking closely at every appearance Donald Trump and Hillary Clinton make with potential running mates. Also in the news: Bernie Sanders on Tuesday is expected to finally endorse the former secretary of state. Gwen Ifill talks with Tamara Keith of NPR and Amy Walter of The Cook Political Report.