 are supposed to take hurricane force winds. At the peak of the outages, more than 2.2 million CenterPoint customers were without power. That's more than when Hurricane Ike, a Category 4 storm, hit Houston in 2008. I'm Dominic Anthony Walsh in Houston. The House of Representatives has passed legislation that requires voters to show proof of U.S. citizenship before they cast a ballot. The measure now heads to the Senate. NPR's Windsor Johnston reports the issue has been promoted by Republicans.