Senate Republicans on Thursday rejected an amendment to the ObamaCare repeal bill that would have tied it to a separate fight on blocking suspected or known terrorists from being able to buy guns.

The California Democrat's proposal, which she has also introduced as a separate piece of legislation, would allow the attorney general to block the sale or transfer of a gun or explosive to a suspected or known terrorist if the individual is believed to use the weapons in an act of terrorism.

Speaking to reporters earlier Thursday, Feinstein called her amendment "the definition of a no-brainer."

She underscored the bipartisan support behind the proposal, pointing out that a House Republican has introduced a similar bill and the idea was initially backed by the Bush administration's Department of Justice in 2007.

"This is not the way we're supposed to do things in this country," he said ahead of the vote.

- This story was updated at 7:36 p.m.