The partisan political debate over potential changes to how Pennsylvania registers voters and runs elections moved Thursday from the Capitol in Harrisburg to suburban Philadelphia, where the leading House Republican on the topic showed up at a news conference by Democratic Gov. Tom Wolf.

House State Government Committee Chairman Seth Grove, R-York, tweeted out a defense of the 149-page revamp of election law that he rolled out more than a week ago, as Wolf and his fellow Democrats denounced the proposal.

"We have a great bill that addresses election issues which voters support!" Grove tweeted...