Thursday's first replay of the issue since that 2013 vote showed an erosion of support by seven votes since then and came in what is now a Republican-run Senate. The issue has never received a vote in the GOP-run House.
With next year's presidential and congressional elections moving into sight, Democrats have hoped that support for the curbs would grow, fed by a spate of high-profile mass slayings since 2013.
Also feeding public anxiety has been last month's attacks in Paris, which left 130 people dead and has raised concerns about a growing threat posed by armed groups like the Islamic State in Iraq and the Levant (ISIL).
The Manchin-Toomey proposal would require background checks for all gun purchases online and at gun shows. Currently, the checks are only required for transactions from licensed gun dealers.
Thursday's vote was symbolic because the proposal was offered as an amendment to a bill obliterating President Barack Obama's health care law, which he will veto. Nonetheless, its political significance was unmistakable.
Sens. Susan Collins of Maine, Mark Kirk of Illinois, John McCain of Arizona and Toomey were the only Republicans to support the proposal. Sen. Heidi Heitkamp of North Dakota was the only Democrat who opposed it. Sens. Ron Johnson, R-Wis., and Mark Warner, D-Va., did not vote.
The vote came a day after a shooting in San Bernardino, California, killed 14 people and wounded 21 others.
Earlier Thursday, the Senate in mostly party-line votes rejected rival proposals that could make it harder for people the government suspects of being terrorists from purchasing firearms.
By 54-45, senators voted down a proposal by Sen. Dianne Feinstein, D-Calif., that would let the government bar sales to people it suspects of being terrorists. Though she initially introduced the proposal early this year, it received attention after last month's attacks in Paris.
Minutes earlier, the Senate killed a rival plan by Sen. John Cornyn, R-Texas, that would let the government delay firearms sales to suspected terrorists for up to 72 hours. Under that proposal, the transaction could be halted permanently during that waiting period if federal officials could persuade a judge to do so.
Senators voted 55-44 for Cornyn's proposal, but it needed 60 votes to pass.
Democrats said Cornyn's proposal was a sham because it would be easy for a lawyer to force enough delays to last 72 hours and let gun purchases proceed.
Republicans said the government's terror watch lists include people who are included erroneously and should not be used to deny people their right to own firearms.
The Associated Press