Democratic presidential candidate Bernie Sanders addresses a rally Wednesday at the Santa Clara County Fairgrounds in San Jose, Calif. The senator's campaign is intently focused on a big win in the state on June 7, and has poured money into TV ads there. Josh Edelson/AFP/Getty Images hide caption

toggle caption Josh Edelson/AFP/Getty Images

Donald Trump arrives at the Republican National Committee headquarters on Capitol Hill last week to meet with House Speaker Paul Ryan and other GOP leaders. Nicholas Kamm/AFP/Getty Images hide caption

toggle caption Nicholas Kamm/AFP/Getty Images
'Highly Sophisticated Killers' No More. Trump Embraces Big Donors
  • Download
  • <iframe src="https://www.npr.org/player/embed/478560644/478571309" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

A voter enters a polling place on May 3 in Whiting, Ind. Older voters feel that the issues that concern them haven't been mentioned enough on the campaign trail. Scott Olson/Getty Images hide caption

toggle caption Scott Olson/Getty Images
Older Voters To Candidates: Don't Forget About Us
  • Download
  • <iframe src="https://www.npr.org/player/embed/478410141/478562686" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript

A demonstrator holds a "Stop Trump 2016" sign across the street from an April 25 Donald Trump rally, in West Chester, Pa. Bloomberg/Bloomberg via Getty Images hide caption

toggle caption Bloomberg/Bloomberg via Getty Images
Progressive SuperPACs Ramp Up Their Big-Money Effort Against Donald Trump
  • Download
  • <iframe src="https://www.npr.org/player/embed/477758538/477758539" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
  • Transcript