In Pennsylvania, Democrat Barack Obama has opened up a big, early lead over Republican John McCain - in the number of local offices.

Obama has 24, McCain has three, not counting an additional seven that serve all Republican candidates.

Whether this gap ultimately makes any difference as to who wins Pennsylvania's 21 electoral votes Nov. 4 remains to be seen.

But Obama's strategists say the offices are part of a highly structured, volunteer-heavy plan to help carry a state that is must-win for Obama and high on McCain's wish list.

In a conference call with reporters yesterday, Craig Schirmer, who is running Obama's Pennsylvania campaign, laid out a plan to create more than 700 neighborhood teams to cover the state.

The teams will engage in canvassing, house meetings, church visits, phone banks, and the recruitment of additional volunteers.

Schirmer said 247 of the teams are in place, with captains committed to spending 10 to 20 hours per week on campaign work for the duration.

The Obama campaign also plans to go after the roughly one million Pennsylvanians of voting age who have not registered. Already this year, statewide voter registration is up a net of 215,000, with Democratic registration up 317,000.

Schirmer called the overall blueprint a combination of "new technology and old-style organizing principles."

The McCain campaign promises strong outreach efforts of its own; in 2004, the campaign to reelect President Bush made highly effective use of local supporters in their voter-contact efforts, taking care to see that targeted voters heard from neighbors with similar interests.

And through his own campaign schedule, McCain has made clear that he places a premium on taking Pennsylvania out of the Democratic column.

McCain has come to the state four times since the middle of June and has maintained a large and sustained presence through television commercials. His strategists see opportunities to make inroads in the socially conservative, older and nominally Democratic counties in northeastern and Western Pennsylvania.

"You're just starting to see the tip of the iceberg," McCain's state campaign manager, Ted Christian, said of visits by the candidate and surrogates. "I think he'll open his own post office box here. This state is of the utmost importance to the senator."

Polls show Obama ahead in Pennsylvania, with the most recent survey giving him a six-point lead. The Democrats have won the state in the last four presidential elections, although John Kerry's margin of victory four years ago was only 2.5 percentage points.

Gov. Rendell, who backed Sen. Hillary Rodham Clinton in the Democratic primaries, described himself as "confident . . . but not overconfident" that Obama would win the state, calling McCain "as appealing a Republican candidate as they've run in the last 20-odd years."

McCain has one area office, in Blue Bell, Montgomery County. More are expected.

Obama has eight: three in Montgomery County, two in Delaware County, and one each in Bucks County, Chester County and Center City.