Oregon's continuing debate over gun control will almost certainly intensify following Tuesday's shootings at Reynolds High School in Troutdale.

"When it hits home like this we can't let it go on," said state Sen. Ginny Burdick, D-Portland, the Legislature's most ardent supporter of new restrictions on guns. "We lost another child today."

Oregon legislators have bitterly fought over gun issues over the last two years following the mass shootings at Newtown, Connecticut, and the Clackamas Town Center in suburban Portland.

Opponents of additional gun restrictions have bottled up bills calling for stricter criminal background checks for gun purchasers. Attempts to find middle ground by focusing on keeping firearms out of the hands of those with mental illness have foundered.

House Judiciary Chairman Jeff Barker, D-Aloha, and a critic of gun control, agreed that Tuesday's shootings would put additional pressure on legislators to deal with the issue.

"I want to do something that is effective," said Barker. "For most of the people involved in these shootings, a background check wouldn't keep them from doing what they did."

Burdick and other supporters of requiring background checks on a wider range of private sales argue that such laws do make a difference. They cite studies showing lower rates of gun violence in states with more comprehensive gun regulations.

TROUTDALE, OREGON - June 10, 2014 - Family and friends of Reynolds High School students are reunited with them after a deadly shooting at the school. Faith Cathcart/The Oregonian

Several polls have shown strong support in Oregon for expanding background checks and for reducing access to guns by those who are mentally ill. A poll taken for The Oregonian six weeks after the Newtown and Clackamas shootings also found that a relatively narrow majority of Oregonians supported restrictions on the size of gun magazines and on military-style, semi-automatic rifles. In addition, Oregonians favored, 52 percent to 40 percent, prohibiting concealed handgun licensees from carrying guns into school.

Despite such polling, opponents of gun control, aided by the powerful National Rifle Association, have been more ardent in their opposition. Barker noted that he received 1,600 emails in one day opposing a 2013 bill that proposed several new restrictions. The measure immediately died without a hearing.

In the last two years, however, gun-control advocates have stepped up their organizing efforts around the country, including in Oregon.

"We are calling for people to become single-issue voters" in support of new gun regulations, said Kylie Menagh-Johnson, a Portlander who is a regional manager for Moms Demand Action for Gun Sense in America.

The group, formed after the Newtown shootings, now has chapters in every state and recently joined an organization, Everytown for Gun Safety, financed by former New York Mayor Michael Bloomberg.

Family members of the two victims of the Clackamas mall shootings formed a group called Gun Owners for Responsible Ownership and have frequently testified at the Legislature.

"It's almost like reliving that day again," said Jenna Yuille, the daughter of Cindy Yuille, one of the Clackamas shooting victims. She said she and her stepfather, Robert Yuille, and Paul Kemp, the brother-in-law of Steve Forsythe, also killed at the mall, believe that expanded background checks would be a good first step. She said the group also wants laws making gun owners liable if they don't safely store their guns.

Menagh-Johnson said she also works in Washington and Nevada, two states that had nationally publicized shootings within the last week.

Two police officers and another man were gunned down in Las Vegas on Monday by a couple professing strident anti-government sentiments. One student at Seattle Pacific University was killed and another injured by a gunman prosecutors say was inspired by other mass shootings.

Menagh-Jonson said the events, tragic as they were, have spurred activists to take action. One political test will come this year in Washington, she noted, when voters will decide whether to toughen that state's law on background checks.

State Sen. Brian Boquist, R-Dallas, said he's had a number of conversations with both supporters and opponents of gun control to try to find solutions everyone can agree on.

But he said lawmakers have found it hard to get a handle on the mental health system and find money to improve it. He said he's also run into the same problem trying to go after people who try to buy a gun and fail the background check because they have something like a felony in their background.

"Nobody's got any money to prosecute these people," he said.

Two Oregon Democrats in Congress were also quick to call for action at the national level following the Reynolds shooting.

U.S. Rep. Earl Blumenauer, whose district includes the high school, said on Twitter:

"Another shooting. I always hope tragedy will inspire action. Simple common sense steps make difference. Start w/universal background checks."

"As these deadly events increase in frequency, it is unconscionable for us to sit by and do nothing," said U.S. Rep. Suzanne Bonamici of Washington County. "Expanded background checks and expanded access to mental health care could help prevent these terrifying incidents."

Several gun-rights supporters criticized quick calls for action, saying that lawmakers shouldn't be politicizing the tragedy. "You have no facts and you jump in to take advantage of a tragedy for cheap political points," said Jeff Reynolds, the Multnomah County Republican chairman, responding to Blumenauer in a Twitter message.

-- Jeff Mapes