This is what the US vice president actually does -- and how the job has changed

AP/Jessica Hill With the final round of the presidential race almost certain to pit Donald Trump and Hillary Clinton in contest for the ultimate prize, arm-chair analysts and other peanut gallery stalwarts are now speculating about an almost equally intriguing question: who the presumptive nominees will select as their running mates.  Will Trump pick an insider like Newt Gingrich, or another brash outsider like himself? Will Hillary Clinton try to eat away at Trump's white, male voter base�...