OLYMPIA, Wash. — TV and radio ads in support of an initiative to prevent the expansion of gun sale background checks will begin next week, the campaign announced Thursday.

Protect Our Gun Rights sent an email to supporters telling them about the ads that will begin Monday and will initially run a week unless they can raise more money to keep them going longer. The group is behind Initiative 591, which would also prohibit confiscation of firearms without due process.

The group said that the TV ad will run statewide on FOX News, and that it will run on CNN, HLN and CNBC in western Washington. The radio ads will run on stations in Seattle, Olympia, Spokane and Vancouver, said Alan Gottlieb, chairman for Citizens Committee for the Right to Keep and Bear Arms, who is leading the campaign for I-591.

The 30-second ad cites endorsements by the Washington Council of Police and Sheriffs and the Washington State Law Enforcement Firearms Instructors Association.

I-591 is competing against Initiative 594, which is pushing for universal background checks on gun sales and transfers.

Supporters of that measure have raised more than $6 million, including an influx of cash from prominent figures, including Microsoft co-founders Bill Gates and Paul Allen, and former Microsoft CEO Steve Ballmer.

I-591 has raised about $1 million so far. Gottlieb said that the combined ad buy for next week cost $36,000.

“We know how much money the other side’s got,” he said. “We’re going up early, because we need to raise enough money to keep it going the whole campaign.”

Zach Silk, the campaign manager for the Washington Alliance for Gun Responsibility, said that I-594 supporters plan to have their own TV ads up in early September as well.

“We anticipate that we’ll be very competitive as we get into the rest of this campaign,” he said.