Democrats Plan to Pursue Most Aggressive Gun-Control Legislation in Decades

“This new majority is not going to be afraid of our shadow,” said Mike Thompson, a California Democrat who is chairman of the House Gun Violence Prevention Task Force. “We know that we’ve been elected to do a job, and we’re going to do it.”

Mr. Thompson, who represents a district in the Napa Valley north of San Francisco, said he plans to introduce legislation mandating universal background checks in the opening weeks of the new Congress.

The gun-control movement’s evolution was evident this week following news that a dozen people had been killed Thursday at a country music bar in Thousand Oaks, Calif.

While in the past there were calls for time to mourn victims following mass shootings, this week advocates reacted instead with a call for new legislation.

Susan Orfanos, whose son was killed Thursday after surviving the Las Vegas massacre last year, said in a television interview that she doesn’t “want prayers. I don’t want thoughts. I want gun control, and I hope to God nobody sends me anymore prayers.”

Opponents of new gun laws say additional restrictions are unnecessary.

Tennessee Rep. Marsha Blackburn, a Republican whose victorious Senate campaign Tuesday was backed by $2.5 million in spending by the NRA, was asked on Fox News what can be done to prevent gun violence like the Thousand Oaks shooting.

“What we do is say, how do we make certain that we protect the Second Amendment and protect our citizens?” Ms. Blackburn replied, referencing the U.S. Constitution plank that grants the right to bear arms.

About 61% of voters participating in the 2018 midterm elections said America’s gun laws should be stricter, according to AP VoteCast, a pre-election and Election Day survey of about 90,000 people who said they voted or intended to vote. About 13% of Democrats and 8% of all voters said gun control was the most important issue affecting their vote.

The 2018 elections marked the first time gun-control advocates outspent the NRA.

The gun-rights advocacy group spent about $20 million in the 2018 election cycle—much of it on advertising backing the confirmation of Supreme Court Justices Neil Gorsuch and Brett Kavanaugh, NRA spokeswoman Jennifer Baker said.

Everytown for Gun Safety, the gun-control organization backed by former New York City Mayor Michael Bloomberg, and a group founded by former Democratic Rep. Gabrielle Giffords, who was critically wounded in a 2011 shooting, spent a combined $37 million in 2018.

Ms. Baker said she is optimistic NRA-backed candidates will prevail in governor’s races in Florida and Georgia that have yet to be called. The NRA also invested in GOP Senate candidates who ousted Democratic incumbents in Indiana, Missouri and North Dakota. NRA-backed Senate candidates lost in Montana and West Virginia.

“The biggest Second Amendment implication of the election is that the pro-Second Amendment majority in the U.S. Senate will continue to confirm pro-Second Amendment judges to the lower courts all the way to the Supreme Court,” Ms. Baker said.

At the state level, voters in Washington state approved a ballot referendum expanding the state’s requirement for background checks on gun purchases. In Florida, Democrat Nikki Fried leads the race for agriculture commissioner, whose office regulates the state’s concealed weapon permits.

The highest-profile gun-control advocate on the ballot Tuesday was Democrat Lucy McBath, who defeated GOP Rep. Karen Handel in a suburban Atlanta House contest. Ms. McBath, a former Delta Air Lines flight attendant, became a gun-control advocate after her teenage son, Jordan Davis, was shot and killed in 2012 by a man who said the boy was playing music too loud. The assailant was later convicted of murder.

Ms. McBath, who became a spokeswoman for Everytown and a 2016 campaign surrogate for Hillary Clinton, relayed her story on the campaign trail and in her early television advertisements. But in the closing weeks before Election Day, Ms. McBath focused on health care and economic issues.

Everytown’s closing TV ad backing Ms. McBath didn’t mention gun control, focusing instead on health care. “Voters absolutely understood where Lucy stood on the issue of gun safety,” said Everytown President John Feinblatt. “There was no question in voters’ minds about Lucy’s story.”