Gov. Ed Rendell yesterday promised to veto a bill that would require all Pennsylvania voters to show identification at the polls, calling it an unconstitutional government "encroachment" on the right to vote.

In Presidents Day appearances in Philadelphia and Pittsburgh, the governor warned of the possibility of widespread disenfranchisement of poor and elderly citizens in arguing against the bill, which cleared the state Legislature last week largely along party lines.

"If this bill had become law, some people would have been denied the right to vote," he told a large crowd at the Hill House in Pittsburgh's Hill District. "At a time in our nation's history when voter participation is dropping to alarming levels, we should be doing everything in our power to make it easier to vote."

The bill's supporters see it as a defense against voter fraud. It also has provisions that give military personnel stationed overseas more time to vote by absentee ballot.

"It's a false argument to say anybody is going to be disenfranchised. The only ones that are going to be disenfranchised are the ones trying to commit fraud," said Steve Miskin, spokesman for House Majority Leader Sam Smith, R-Punxsutawney. "What are [Democrats] hiding from? What are they scared of?"

Democrats weren't the only ones expressing fears about the bill. Many voting rights and community organizations said the ID requirement would discourage poorer people, who are less likely to carry identification, from going to the polls.

Those groups -- including the Black Political Empowerment Project, ACORN, Pittsburgh Interfaith Impact Network, the League of Women Voters and VotePA -- have been lobbying Mr. Rendell for months.

Members of those groups packed the Hill House's auditorium yesterday afternoon. They gave the governor a standing ovation and sustained applause.

Currently, only people voting in a polling place for the first time must show identification. If a voter doesn't have ID, he or she can use a provisional ballot. Election officials don't count the ballot until they verify the voter's registration status.

The legislation passed last week would allow a range of identification types, including a valid driver's license; a U.S. passport; a student, employee or government ID; a county voter registration card; a firearm permit; a current utility bill; or a current bank statement, paycheck or government check.

It also would allow registered voters to apply for a free, non-photo ID issued by the Pennsylvania Department of Transportation.

Anyone without proper ID could still cast a provisional ballot.

"We heard your concerns and dramatically loosened the identification requirements," state Rep. Stephen Barrar, a Republican from Delaware and Chester counties, said in a letter to Mr. Rendell last week. He also said the bill would guarantee that soldiers fighting overseas would have time to vote.

In a letter to lawmakers explaining his veto, the governor said: "Regardless of how long the list of acceptable forms of identification is, there are people who may not be in a position to produce any of them."

At the Hill House, he said there were other bills before the state Legislature that, if passed, would make it easier for military personnel to vote. He criticized Republicans for tying the issue to voter identification.

He also argued that there have been no examples of fraud that make voter IDs necessary.

"I veto this bill today because it is designed to cure a harm that does not exist," he said.

Erik Arneson, spokesman for Senate Majority Leader David J. Brightbill, R-Lebanon, said the bill was designed to combat fraud by putting "protections in place before things happen."

He also said that by focusing on the ID element of the bill, Mr. Rendell ignored other changes contained in the legislation, like banning polling stations from the private homes of elected or appointed party officials, candidates, elected officials or places that are inaccessible to the physically disabled.

It's unlikely that bill supporters will be able to muster enough votes to override the veto, Mr. Arneson said.