The plaintiffs — eight registered Democrats, plus the Homeless Advocacy Project, the League of Women Voters of Pennsylvania and the Pennsylvania chapter of the National Association for the Advancement of Colored People — had sought to block the law from taking effect in this year's election as part of a wider challenge to its constitutionality.
Republican Gov. Tom Corbett signed the law in March after every single Democratic lawmaker voted against it.
The prior law required identification only for people voting in a polling place for the first time and it allowed nonphoto documents such as utility bills or bank statements.
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