There is much that separates Montgomery and Prince George’s counties, but on one particular goal for the coming Maryland General Assembly session, they are united: Both want more transportation funding.

Officials from both counties said they will push hard for money to develop the Purple Line rapid-transit system, which is envisioned as an east-west link between the two counties.

Prince George’s officials say the county also urgently needs funding for roads around a proposed casino at National Harbor.

In Montgomery, there is an effort to build the Corridor Cities Transitway, which would link up the county’s fast-growing biotechnology corridor with the Metrorail system.

Prince George’s County Executive Rushern L. Baker III (D), who has advocated expansion of the county’s commercial sector, said his plans for luring development could be thwarted without an increase in state transportation funds, which have dried up without any plan to replenish them.

“We cannot do any economic development project without transit funds,” he said in an interview.

In Montgomery, there is a similar sentiment. “We’re reaching the point of crisis about transportation,” said Sen. Jamie B. Raskin (D-Montgomery), Senate chair of the county legislative delegation.

To get the money, officials from both jurisdictions said, they would support an increase in Maryland’s gas tax. The 23.5 cent-a-gallon tax has not been altered in 20 years, despite the growing cost of building and maintaining roads and expanding public transportation throughout the suburbs.

In the most recent legislative session, Gov. Martin O’Malley (D) led an unsuccessful effort to apply Maryland’s 6 percent sales tax to gasoline, just as gas prices were spiking. Now, with fuel prices down, the mood might be different, Baker said, adding that he would consider supporting any proposal to boost funds for transit and roads.

Securing transportation funding next year is critical, said Melanie Wenger, Montgomery County’s director of intergovernmental relations. Wenger said the state usually allocates about $30 million to $40 million a year to Montgomery, but the county needs much more.

And because an election year looms in two years, this is the session to make significant investments.“This is starting to be the year that something has to happen,” she said. “You don’t get something going this year, and, I think, you are waiting for a while.”

Wenger’s office released a pamphlet titled “Invest in Montgomery.” In it, county officials urged state legislators to create a plan to produce “significant and sustainable state revenues” for transportation projects.

Without the Purple Line, the CCT and other transportation projects, developments such as the Great Seneca Science Corridor and the White Flint makeover won’t prosper, the pamphlet says.

“For Montgomery County to continue to thrive as the state’s key economic engine, the State must be a full partner in investing in the County’s capital infrastructure,” the pamphlet says. “Without a stronger partnership, Montgomery will struggle to maintain its ability to compete regionally, nationally and globally.”

On other issues expected to arise during the 2013 legislative session, the interests of Montgomery and Prince George’s sometimes coincide and sometimes don’t.

Both counties, for instance, expect to push to abolish the death penalty. “It is time for us in Maryland to do away with this,” Baker said. “It is bad policy.”

But Baker is also hoping that the state will iron out what he considers an inequity in a formula that measures the wealth of counties based on tax returns and that is used to determine the amount of state aid.

For years, Montgomery has benefited from the number of county residents who ask for extensions and file their income tax returns late — mostly because they owe money. In less-affluent Prince George’s, residents are more likely to rush to file returns in order to get refunds.

Because its residents’ tax filings are less complete, Montgomery looks relatively less affluent than it is and gets more state aid. Prince George’s, on the other hand, looks relatively more affluent than it is and gets less funding.

Baker believes that O’Malley has promised an adjustment that will help Prince George’s without penalizing Montgomery, but it remains unclear exactly how the state budget would pay for it. If the formula is changed, it could mean as much as $20 million in increased state aid for Prince George’s in the next fiscal year, a substantial addition to the county’s $2.7 billion budget.

Although Baker expects to be able to work closely with other jurisdictions to find new sources of transportation funds, Prince George’s will be competing with its neighbors for money for schools and for its proposed new regional hospital.

O’Malley has committed to providing $200 million in state money for the $600 million regional hospital. Prince George’s and the University of Maryland Medical System, which is supposed to operate the medical center, would pay the remaining two-thirds.

In other matters, members of the Montgomery delegation were among a group of state senators, led by Sen. Brian E. Frosh (D-Montgomery), calling for an assault weapons ban, tighter regulations on firearms dealers and other gun-control measures.

Raskin said he will introduce the assault-weapons ban on the first day of the session. Although a ban did not pass in 2010, Raskin said he believes that the shootings in Newtown, Conn., have created “sufficient momentum.”

“If we can’t act now, when can we act?” he asked.

Montgomery is also requesting $147 million for capital projects for the county school system and seeks funding for expansion projects at the Universities at Shady Grove and the Rockville and Germantown campuses of Montgomery College. “That’s pretty high on the list,” County Executive Isiah Leggett (D) said.

Funds also are needed to rebuild and repair Prince George’s schools, Baker said. Baker, the County Council and the school board recently requested nearly $100 million for school construction. That is more than double its request last year, when the county received about $36 million.

Baker said he will renew an effort to approve a 5-cent bag fee on disposable shopping bags, a position that has cost him some support. An intense ad campaign this year by the plastics industry helped sway the county delegation in Annapolis against a bag fee, which opponents called a regressive tax on the poor.

Legislators will be pushing to allow slot machines at veterans organizations in Montgomery. When the General Assembly expanded gambling in a special session over the summer, it allowed many veterans organizations in Maryland to operate slot machines. Veterans’ halls in Montgomery were an exception.