Doug Duncan, Montgomery county executive and would-be governor of Maryland, is the No. 1 booster of the new Silver Spring. After all, Duncan's the guy who took a sad old suburban downtown and transformed it into a people magnet with a burgeoning arts scene, sparkling new shops and a steady influx of jobs. The story of how Silver Spring sprung will be one of Duncan's top sales pitches in the coming campaign.

But other than being from the county that the rest of Maryland loves to hate, Duncan's greatest vulnerability in his Democratic primary race against Baltimore Mayor Martin O'Malley next year will be his reputation as a big -- make that huge -- spender. Duncan may be the man who brought Montgomery a world-class concert hall, but multimillion-dollar cost overruns for the Music Center at Strathmore -- along with similar budget-busting on the Black Rock Center for the Arts in Germantown, a renovated detention center in Rockville and downtown Silver Spring's showpiece, the Silver Theatre -- make a fat target for political opponents.

Luckily for Duncan -- and not so happily for Silver Spring residents -- the new downtown gives the county executive a chance to prove he can also be frugal and tough.

For years, Silver Spring residents fought off some nutty ideas for remaking their downtown. The wacky American Dream megamall proposal envisioned a 27-acre enclosed complex, including an indoor roller coaster, wave pools for 3,000 swimmers and enough shops to suck the life out of much of southern Montgomery.

Residents finally embraced a much more modest plan focused on the arts -- the American Film Institute's movie complex, the Round House Theatre and the Discovery Channel headquarters. But to win local support for the plan, the county had to promise to build a civic building with an outdoor skating rink and concert pavilion.

Now, with the arts and retail pieces of the new downtown built and thriving, the gaping hole in the center is that civic building site. With that project's cost escalating from $12 million to $16 million, Duncan has decided to scrap the ice rink and pavilion, taking the project back to its original budget level.

"My instructions to staff were, 'Do whatever we can to bring things in at the original cost,' " Duncan says. "People have been questioning why we're not facing reality here, and they were justified in asking. The people of Silver Spring -- I'm sorry -- are the first to feel the effect of this."

Duncan argues that if things turn around, the rink and pavilion can be added later, and anyway, "Silver Spring is doing very well. Thousands of people go there every day."

That attitude drives some residents up a wall. "The skating rink has been the lure for our support for years," says Gail Gugel, vice president of the Seven Oaks-Evanswood Civic Association. "We have all this traffic and development, and the payoff was going to be a nice downtown with resources for residents like a rink and a pavilion.

"People in Silver Spring feel that things happen here that they wouldn't dare do in Bethesda, Chevy Chase or Potomac. They think we're going to roll over just because it's Silver Spring."

Derick Berlage, chairman of the county Planning Board, argues that Duncan is right to draw a line and stick to a budget. "This was a promise to the community, but it's apparently a promise that can't be fulfilled," he says. Silver Spring is such a success -- condos, lofts, restaurants and mixed-use projects are popping up all over -- that "this community sooner or later will get the amenities they want."

Sooner or later is not enough for those who were given a promise. "Doug staked his reputation on Silver Spring," says County Council Chairman Tom Perez, whose district includes downtown. "I can understand that Strathmore became the metaphor for large public investment in a time of wealth. And it's easy to say that Silver Spring has sprung and we don't need to jump-start the development anymore. But there was a commitment made to the community. This isn't dead yet."

Duncan must decide which is more important -- keeping that commitment or demonstrating his ability to wield the scalpel. He has to think not only about what Silver Spring residents want, but also about what O'Malley and Gov. Bob Ehrlich would do.

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