The most important question to be decided in the current Philadelphia mayoral campaign may have less to do with the candidates than the voters.

It is this: Do Philadelphians realize this election is a matter of life or death for the city?

Two recent reports provide some heartening evidence that at least the city's prime decision-makers understand what the stakes are, though the reports also provide some unnerving information about the dimensions of the challenge ahead.

Here's what's at risk: As the United States moves from the industrial to the information age, it needs fewer cities, and only those cities that can become attractive and efficient marketplaces for the new era will make the cut. Nowhere is it written that Philadelphia must continue to be a major city.

And while many different ingredients will go into determining whether a given city will continue to be a desirable place to work and do business, it starts with having an effective mayor.

So where does Philadelphia stand, according to these reports, as we head into this Gotterdammerung of an election?

"We are in contention, but we are not gaining on anyone," says John Claypool, executive director of Greater Philadelphia First, commenting on his organization's "Regional Economic Benchmarks" report, issued in July.

(While most of the measurements are for the entire metropolitan area, they generally portray the situation facing city residents.) The Philadelphia region slipped a little since last year's report, to 44th from 43d out of the 50 largest metropolitan areas, on the report's spotlighted "income opportunity index." This is an amalgam of wages, living costs and employment levels that shows where economic advancement is most likely.

On the other hand, the report finds that the Philadelphia region has a lot of small, fast-growing companies, which it calls "gazelles," indicating a potential for more rapid growth in the near future than many of the cities we compete against.

It also shows the Philadelphia region holding its own against many of its prime competitors in those fields Claypool's organization regards as crucial to the region's economic future: professional and data-intensive services, health care, precision manufacturing and tourism.

Claypool says the report should be an antidote to the bitter despair that gripped the city before Ed Rendell became mayor, while alerting Philadelphians that other regions have not been standing still while Philadelphia's has been moving forward.

A new report done for the Pew Charitable Trusts that focuses on just the city says much the same thing. The report, called "American Cities in the 21st Century," does an exhaustive comparison of Philadelphia and six of its major competitors: Atlanta, Boston, Baltimore, Cleveland, Detroit and Pittsburgh. It concludes that Boston is doing the best among these cities, and Detroit the worst, with everyone else - including Philadelphia - somewhere in between.

In analyzing Philadelphia, the Pew report emphasizes a point that is very much at issue in the mayoral race.

"Philadelphia needs to reduce its tax burden," it says. "It is simply not competitive with its suburbs, nor with most other cities."

The city's "disastrously high" wage tax, coupled with a "business privilege" tax that makes companies pay whether they're making money or not, are a big part of the reason the city is a particularly hostile place for anyone thinking of starting a new business.

The Pew report quotes business leaders as saying, in effect, that an entrepreneur would have to be crazy to start a business here. The GPF report underscores this by noting that while Philadelphia is the nation's fifth-largest city, it ranks much lower in start-ups.

The Pew report goes on to emphasize the importance of reducing crime, improving education and upgrading infrastructure, and it raises an issue voters can't do much about: the allegedly "second-rate" caliber of the city's business leadership.

It comes to the pessimistic conclusion that "the balance between the positive and negative factors seems to be decidedly negative" at present.

But then it quotes a former city official, who sees things in a more promising light. "Eight years ago, when this mayor took office, the situation, if anything, was much worse," he says. "If anyone said then that the city would be where it is now, solvent and moving ahead on many fronts, they'd have been laughed at. We did what we were told was impossible. We worked at it, made things happen, kept going. It's the same way now."