RENEE MONTAGNE, HOST:
A judge in Pennsylvania has blocked a key part of that state's new voter ID law, a law that's caused controversy. Now, come Election Day, voters showing up at the polls can still be asked to show a government-issued photo ID, but they will not be prevented from voting if they don't have one. NPR's Pam Fessler has been covering the story and she joins us now. Good morning.
PAM FESSLER, BYLINE: Good morning.
MONTAGNE: So, remind us what this Pennsylvania law is - you know, why it's been making national news.