PHILADELPHIA - At Sneaker Villa, a Philadelphia-based sportswear chain where the voter-registration forms sit in a counter display near boxes of Adidas throwback shoes, the idea of playing defense, or stopping your opponent from running up the score, seems a natural fit.
"We've given out a little over 1,000 forms," said Sneaker Villa president Jason Lutz, a Barack Obama supporter with a target of enlisting 2,000 of his young, largely minority customers to vote before tomorrow's registration deadline. "So we have a little work to do."
Obama's campaign has given every indication that he does not expect to win the most delegates when Pennsylvania votes on April 22, due to an overwhelmingly white, working-class electorate that has already given Hillary Clinton a sizable lead in some polls. But Obama's team has put to work an intense registration program designed to achieve a broader strategic goal: limiting the scale of Clinton's win to maintain Obama's national edge in the number of total votes cast in the Democratic primaries.
That contest for total votes, while meaningless in any formal sense, is a key to Clinton's strategy for wooing superdelegates by convincing them that she has the broadest strength among voters.
"In this state right now, his game is about bringing the popular-vote differential down," said Ken Smukler, a Pennsylvania Democratic strategist unaligned with either candidate. "Since Super Tuesday, this game has never been just about pledged delegates."
Clinton backers have been increasingly direct in suggesting that they intend to use the candidates' popular-vote totals as indicators of national support when making a case to superdelegates at the primary calendar's conclusion in June. By that point, Clinton will almost certainly have failed to equal Obama's tally of elected delegates, supporters of both candidates acknowledge.
"If Senator Obama wins the popular vote, then the choice will be easier," Bill Clinton told ABC News recently. "But if Hillary wins the popular vote but can't quite catch up with the delegate votes, then you have to just ask yourself, 'Which is more important, and who is more likely to win in November?' "
Obama currently leads Clinton by about 700,000 votes, according to most estimates, without counting results in Michigan and Florida, where efforts to schedule new contests were all but defeated last week. Strategists say that Obama's popular-vote lead will be difficult for Clinton to surmount without a run of massive victories.
"What she wants to do is run up numbers here," said Neil Oxman, a Democratic media consultant in Philadelphia not working for either candidate. "It's not only a delegate fight for her, it's a popular vote fight for her."
Tomorrow's voter registration deadline will offer both candidates their last chance to shape the electorate by bringing in new voters to a closed Democratic primary, in which only Democrats may vote.
"It's a huge effort," said Seth Williams, a lawyer who coordinated Obama's petition campaign to get on the Pennsylvania ballot. "The entire focus of the field level and the grass roots is to register people to vote."
State officials have already reported an unprecedented flurry of registration activity. Since local elections were held last fall, the statewide Democratic voter rolls have increased by 111,227, while Republicans lost 13,391 of their voters. That swing includes both new voters and 57,651 Pennsylvanians who changed their party identification, largely shifting from Republican or nonpartisan to become Democrats.
In Montgomery County, a key suburban battleground, Democrats have added 4,347 voters since the end of February, according to figures made available by the board of elections late last week.
"The Obama campaign is doing a better job of doing it [in a way that is] organized, but I think Clinton is getting more people who are driven to do it on their own," said Marcel Groen, chairman of the Montgomery County Democratic party and a superdelegate supporting Clinton.
Despite high levels of voters changing their party affiliation to become Democrats, both campaigns have bypassed more ambitious plans to aggressively target individual Republican voters to switch, according to operatives on each side.
The Obama campaign has called independent voters - a relatively small share of the electorate in Pennsylvania, due to the historically dominant role of party machines compared to other states - to become Democrats. Many are believed to be young voters registered under the so-called Motor Voter Act, which encourages applicants for driver's licenses to register to vote but defaults to "nonpartisan" if a new registrant does not select a party.
Both campaigns have concentrated registration efforts in areas of clear demographic strength: Clinton's supporters brought registration forms to St. Patrick's Day parades in Philadelphia, Pittsburgh, and Scranton. "We're going to look to register people from our demographic of those most likely to vote for Senator Clinton," said the campaign's state director, Mary Isenhour, identifying senior citizens and blue-collar workers.
"Running in a state for popular votes is different from running in a state for delegate votes," said Smukler. "Your resources go in the state to different places."
There are only 16 delegates, among the state's total of 158, available in the two congressional districts that include most of Philadelphia, and Obama is expected to win both by sizeable margins, with a likely swing of only one or two delegates per district based on his performance. (Of the total, 55 delegates will be awarded proportionally based on statewide results.) Concentrating more effort there won't win him significantly more delegates.
But Obama's campaign has nonetheless flooded friendly turf in Philadelphia, from the upscale white bastion of Rittenhouse Square to less affluent stretches of North Broad Street, areas with high African-American populations, where Obama operatives associated with congressman Chaka Fattah have led high-profile registration campaigns in the past. For more than a week, Obama has been broadcasting ads on Philadelphia radio stations focused on luring new voters.
"You know what precincts and what areas typically vote Democratic," said Obama spokesman Sean Smith, naming the state's big cities and college campuses. "You basically start with that."
With successful get-out-the-vote operations targeted at an expanded electorate, Obama could develop a lead in Philadelphia of as many as 150,000 votes, a total that could have a meager impact on delegate allocation but make it difficult for Clinton to claim a popular landslide in Pennsylvania, analysts say.
There are nearly 4 million Democrats registered in the state, although officials believe the number is inflated with inactive voters. In the 2002 Democratic gubernatorial primary, the last major contested primary in the state, 1.24 million votes were cast.
In the best-case scenario for Clinton, a high turnout primary might draw as many as 2 million voters, according to strategists. In that instance, keeping Clinton's lead under 10 points, a target privately identified by Obama supporters here, would yield a trove of no more than 200,000 votes toward Clinton's national total.
"If they win Chaka's district 80-20 and that helps them keep down the statewide popular vote to something manageable, that's part of their strategy," Oxman said of Obama's campaign. "They don't want to lose the state 60-40."