Grief, politics and a day of presidential contrasts

( CNN) The gulf between those who have occupied the Oval Office and the individuals who crave it is on rare display Tuesday.

Watch CNN’s town hall with House Speaker Paul Ryan Tuesday at 9:00 p.m. ET

On the campaign trail, Donald Trump and Hillary Clinton are waging the combative politics that has defined a bitter, divisive campaign as they gear up for a crucial three-week period of conventions and vice presidential pickings.