His O'Say Can You See political action committee urged supporters to sign on to O'Malley's petition to Congress. In a message to supporters, the governor wrote that "in the coming months, I'm going to continue to fight for those who stand with us on legislation to reduce gun violence."
O'Malley spokeswoman Lis Smith said that meant "elected like-minded Democrats," a task to which O'Malley has devoted a travel-heavy itinerary this fall.
In the message to supporters, O'Malley praised Maryland's new law, set to take effect next week.
In the wake of last year's Newtown, Conn. shooting at an elementary school, Congress debated but did not pass legislation that would have called for universal background checks in every state.
Maryland already had universal background checks, but state lawmakers endorsed O'Malley's proposal to ban the sale of assault weapons, further limit the size of magazines, require a license and fingerprint to buy a handgun and further restricted who can have access to handguns.