"Instead of unilaterally imposing radical gun control policies on law-abiding citizens, the President should instead focus on prosecuting violent criminals who violate the law," he added. "I oppose this misguided policy and will continue fighting any effort to inhibit law-abiding citizens' ability to protect themselves, their families, or respond to public threats."

The Obama administration's announcement on gun imports and background checks today came after several weeks in which the administration warned that Congress's failure to restrict guns in the wake of several tragedies could lead to executive branch actions.

One of those tragedies was the Newtown, Conn., shooting, and the state's two Democratic senators today praised the announcement.

"The country can't afford to wait," Sens. Richard Blumenthal and Chris MurphyChristopher (Chris) Scott MurphySenate Dem: Graham-Cassidy is an 'intellectual and moral garbage truck fire' Dems call for action against Cassidy-Graham ObamaCare repeal Murphy fires back at Trump on filibuster MORE said. "Nearly nine months after the horrific tragedy of Newtown and in the face of constantly mounting gun violence deaths, we must confront this threat. We have to do something."

The Brady Campaign to Prevent Gun Violence also welcomed the move and said the action to shore up the background check requirement would help keep guns away from felons. The group Moms Demand Action also praised the move, which it said is a step in the right direction.

Political groups today said they would try to raise funds based either on their support or opposition to the Obama administration's decision. Colorado Gov. John Hickenlooper (D) asked people to contribute to an effort to keep Democrats in statewide office who support gun control measures.

The National Association for Gun Rights similarly called on people to oppose the new rules as well as efforts to pass a gun control resolution at the United Nations.