As failed experiments go, it has been rather successful.

Express bus service between Downtown and three suburban areas has drawn substantial ridership in all but one of them over the past two years, putting a dent in the assumption that commuters can’t be coaxed onto mass transit in car-crazy Central Indiana.

While the IndyGo service hasn’t caught on in Greenwood, it has been embraced to an encouraging degree by Carmel and Fishers residents, even allowing for fluctuations with gasoline prices. So why not expand upon it, cutting deeper into oil consumption, traffic congestion, air pollution, highway repairs and aggravation?

Because we’re afraid, locally and statewide, to invest our own money.

Federal funds have made the express service possible. IndyGo announced Monday that the service will die by the end of next year, when the funds run out.

While the service has been operating, advocates of regional mass transit have pushed for increased state and local support for their cause — striking while the iron was hot, if you will. The farthest they got was Indiana House passage this year of legislation to permit local communities to form regional transit authorities with fundraising power.

The bill stalled in the Senate but has support there and needs to be revived. At the same time, efforts must continue to free up a portion of the $4 billion Major Moves highway fund for mass transit.

Federal funds are available as well. But they will go to communities that show commitment by putting up dollars.

What size investment are we speaking of? Charlotte, N.C., parlays a half-cent sales tax into more than $50 million a year for public transportation, a sum exceeding IndyGo’s annual budget.

Big plans for mass transit have been kicked around Central Indiana for years, the latest being the proposed $160 million Northeast Corridor rail line. The community’s failure to sustain express bus service along the same route, at a fraction of the cost, would not bode well for such an ambitious venture. Nor would the larger failure to improve IndyGo as a whole. Having the smallest, most underfunded bus service of any major city amounts to a self-fulfilling prophecy on wheels.

The express service has been a bright spot. Jerking it away rather than exploiting it would break faith with the public, perhaps for good. Government and business leaders must make 2010 the year of connection rather than the end of the line.