HANDOUT IMAGE: Proposed Purple Line route map. (Courtesy of Maryland Transit Administration) (Courtesy of Maryland Transit Administration/COURTESY OF MARYLAND TRANSIT ADMINISTRATION)

FOR MARYLAND Gov. Larry Hogan (R), decision time is approaching for the proposed Purple Line transit project, an east-west light rail link that would run inside the Beltway north of the District. The governor’s verdict, expected next month, will signal whether he attaches more importance to reviving the state’s struggling economy — as he pledged to do as a candidate — or appeasing his mainly rural and exurban political base, for whom transit is no priority.

The 16-mile Purple Line would run between Bethesda and New Carrollton and provide a massive economic shot in the arm to the state’s two most populous jurisdictions: Montgomery and Prince George’s counties, which together account for a third of Maryland’s 6 million residents. They also happen to be the most heavily Democratic counties in the state — and the only ones that voted overwhelmingly for Mr. Hogan’s Democratic opponent last fall.

On the drawing boards for well over a decade, the Purple Line gathered a good deal of momentum, plus pledges of federal and state funding, until Mr. Hogan’s unexpected electoral victory. On the campaign trail, he had expressed doubts about the project’s affordability, which he has reiterated since taking office.

No doubt, at $2.45 billion to build and another $55 million annually to operate and maintain, the Purple Line is expensive. Mr. Hogan is within his rights to ask, as he did, for cost cuts.

But it’s equally valid to assess the cost of not building the line. Its transit advantages have been debated for years, along with the disruptive impact of its construction. That’s a fair debate but also a blinkered one.

Meanwhile, there has been little serious debate about the Purple Line’s potential as a catalyst in rejuvenating and reviving older, close-in suburban neighborhoods that have stagnated as newer communities outside the Beltway have flourished.

On Monday, The Post reported that the region’s population growth has slowed sharply as federal spending has tightened. That makes it critically important that state and local officials do what they can to attract and retain businesses and jobs, and there are few better ways to achieve that than by enhancing infrastructure, especially transit.

A consultant’s study commissioned by Montgomery and Prince George’s concluded that the Purple Line, once operating, could generate 27,000 new jobs annually, along with $635 million a year in higher tax payments. That’s a huge benefit, one that dovetails with the more business-friendly climate Mr. Hogan has pledged.

It’s true that the line would benefit Maryland’s two most heavily Democratic counties, and equally true that Mr. Hogan’s stated preference for building roads over transit is a simple geopolitical preference for localities that tilt Republican.

So for Mr. Hogan, the politically expedient thing to do might be to support his rural and exurban strongholds by laying more asphalt. But there’s little doubt that, for Maryland, the Purple Line’s benefits surpass those of any number of roads he might build through GOP territory.