The Senate Judiciary Committee voted against Northam's bill that would make it a felony to "recklessly leave a loaded, unsecured firearm” in a way that endangers a minor.
“This bill will keep children safe from loaded, unsecured firearms. Like Gov. Northam’s other commonsense gun safety measures, it is something that everyone -- including responsible gun owners -- should support,” said Northam’s spokeswoman, Alena Yarmosky.
The bill is one of eight the Northam has proposed for adoption, drawing the ire of gun-rights activists nationwide.
Two Democrats -- state Sens. Creigh Deeds and Chap Petersen -- joined with Republicans to defeat the measure. They cited concerns that law-abiding gun owners would be unfairly punished.
Another measure that would ban so-called assault weapons like AR-15 rifles is also in danger of falling short. Some of Northam's gun control measures have passed in the state's Democratic-controlled General Assembly and lawmakers will hash out the differences between both chambers in the coming weeks.
Some of the bills include limiting handgun purchases to once a month; universal background checks on gun purchases; and a red flag bill that would allow authorities to temporarily take guns away from anyone deemed to be dangerous to themselves or others.
Thousands of gun-rights activists gathered in the state capital of Richmond last month to protest a push by Democrats to enact tough gun control measures. The gathering prompted Northam to declare a state of emergency days before amid fears of potential violence.
The rally went without incident.
The Associated Press contributed to this report.