Maryland Gov. Martin O’Malley (D) on Tuesday night offered his most expansive argument yet for a major gas tax increase, telling hundreds of the state’s assembled mayors and councilmembers that Maryland must lead by example to keep its bridges and roads safe, and to help create jobs.

“These are the realities we face: We have to close our budget deficit, but we also have to invest in order to create jobs and to make our state stronger,” O’Malley said. “That’s the leadership that our country needs to see from Maryland. More importantly, that’s the leadership that our children need to see from us, especially right now.”

Speaking to the 75th anniversary gathering of the Maryland Municipal League, O’Malley sought to build an ally in advance of an expected fight to convince the General Assembly to approve one or more tax increases in January. He suggested there would be more road maintenance money to go around for municipalities if cities and towns press their state lawmakers to support a gas tax increase.

O’Malley, however, also sought to tap into local leaders’ fears of a transportation disaster if Maryland continues to underfund planned road and transit projects.

“Whether we pay for our infrastructure or whether we pay in so many other ways is up to us,” O’Malley said. “Bridges are not like trees; they don’t grow stronger with age. No, they grow more brittle, and they crumble. And that’s why they need to be repaired before moms and dads die on their way to work and they collapse in rivers,” he said, referring to the 2007 collapse of an interstate bridge in Minneapolis that killed 13 and injured nearly 150 others.

On Tuesday, a blue-ribbon commission set up last year by the legislature and governor finalized a recommendation to increase Maryland’s gas from 23.5 cents to 38.5 cents over the next three years, as well as to hike car registration, inspection and mass transit fares to replenish the state’s underfunded trust for transportation projects.

O’Malley also seized on another commission recommendation to index the gas tax to inflation, saying that a one-time hike may not be enough to close the state’s “investment deficit,” a phrase he has used increasingly in recent weeks to short-hand for his belief that a surge in public infrastructure spending is needed to keep the state competitive and to promote job growth.

“The fact of the matter is, it now costs us more to paint the Bay Bridge than it did to build the first span,” he said.

A traditional flat tax on gasoline, O’Malley said, becomes a declining revenue source, as cars and trucks are being designed to get better gas mileage.

He also said higher revenues will be needed to pay for the Purple Line connecting Montgomery and Prince George’s counties, and the Red Line project to expand Baltimore’s transit system.

“Neither of these projects is free,” O’Malley said.

Maryland needs to increase its transportation spending, O’Malley said, “to look our kids and our neighbors in the eyes … to tell them we’re keeping the faith; that we’re all in this together.”