WASHINGTON — Both of Maine’s U.S. senators said Saturday that they will support a compromise to expand federal requirements on background checks for gun sales, adding two votes to a key component of the gun control package prompted by last year’s mass shooting at a Connecticut elementary school.

Sen. Susan Collins, a Republican, was the first to announce her support for a deal negotiated by two gun-friendly senators last week. Collins, a moderate Republican lobbied by both sides in the gun debate, told NBC News that she would vote in favor of the plan to require background checks for private gun sales at gun shows or that were advertised online or in print. Under current federal law, background checks are only required for gun sales performed by a licensed firearm dealer.

Sen. Angus King, an independent who caucuses with the Democrats, confirmed Saturday night to the Maine Sunday Telegram that he will also support the compromise when it comes up for a vote this week.

Neither King’s nor Collins’ support for the compromise is surprising. Democratic Sen. Joe Manchin of West Virginia and Republican Sen. Pat Toomey of Pennsylvania – the two primary negotiators – addressed a host of issues that Collins had mentioned were of high priority for her.

For instance, the Manchin-Toomey deal would exempt transactions between family members from the background check requirement. The proposal also explicitly prohibits the creation of a “national registry” of gun owners. And the compromise would create a national commission to study the causes of mass shootings, which Collins had called for in the immediate aftermath of the elementary school shootings in Newtown, Conn.

Last week, Collins had called the compromise “very promising” but declined to immediately endorse it. The deal was key to breaking a Republican filibuster of the gun control measure now pending on the floor, setting up votes on individual measures as early as next Tuesday.

“I want to see the actual language because the language is very important,” Collins, who has been the target of lobbying campaigns from both sides, said on Wednesday. “But I think they have made terrific progress in responding to some of the concerns that I have personally had.”

King, who previously called the deal “great news,” has said he would support expanding background checks to private sales but with exceptions for transfers between family members.

Kevin Miller can be contacted at (207) 317-6256 or at:

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