A new poll showing positive suburban views of Philadelphia makes the case for achieving greater cooperation among the region's elected leaders - in Harrisburg, in particular.

In effect, the new Pew Charitable Trusts poll tells suburban Republican leaders that it's OK for them to make common cause with city officials. That's because, according to Pew, "suburbanites think there is a strong link between Philadelphia's future and that of their own communities."

Well, duh?

Not only do thousands of commuters look to Center City for their daily livelihoods, but suburbanites also tell pollsters that they enjoy visiting the city's historic sites, landmarks, theaters, sports events, restaurants, and shops.

It doesn't take a degree in urban planning or sociology to realize that - if those things are important to Philadelphia's neighbors - then it stands to reason that the city's decline would make their communities less desirable places to live. That translates to lower property values and tax revenue, which go toward the support of quality public schools, towns' upkeep, and so on.

There's still little overlap between the two worlds of city and suburb, of course. With rare exceptions, such as the City Avenue special-services district, the notion of regional cooperation to provide public services at lower costs hasn't gotten any traction.

The Pew poll, though, supports the theory that the best hope for a broad-based cooperative effort remains the creation of a regional arts and culture fund, which would support many of the institutions suburban visitors value.

It's certainly a smart move by Mayor Nutter to meet periodically with county officials to discuss as equals regional issues. Ideas for cooperation could arise out of those talks.

As for the political climate, it's certainly too early to predict the end of what might be called doughnut-hole politics. That's where suburban lawmakers set policy in Harrisburg without regard for any negative impact on the city.

But if it matters to their constituents whether Philadelphia sinks or swims, then that should figure into the calculations of suburban lawmakers - especially those who wield power in the capital, such as State Senate Majority Leader Dominic F. Pileggi, from Delaware County.

With Republican Gov.-elect Tom Corbett hailing from the western part of the state, there's a tangible fear that Philadelphia's interests will be shortchanged over the next few years. But now that GOP leaders know that won't sit well with their own constituents, they should stand together with city officials for the region they all call home.