WASHINGTON — The struggle that Sen. Dianne Feinstein, D-Calif., faces in winning approval for a new ban on semi-automatic, military-style weapons was apparent Thursday as soon as she walked into a room to unveil her bill.

No Republican lawmaker was there. Nor was a red-state Democrat.

Her new measure, which goes further than the now-lapsed 1994 law she authored, would prohibit the sale, import and manufacture of more than 150 guns, including the make of Bushmaster rifle used in the Connecticut school shootings, and ammunition magazines that can accept more than 10 rounds.

Those who legally own assault weapons, (not fully automatic weapons like already banned machine guns) would be allowed to keep them. Buyers of currently owned assault weapons would be subject to criminal background checks.

“We have tried to recognize the right of a citizen to legally possess a weapon,” Feinstein said at a Capitol Hill press conference, standing alongside a display of semi-automatic weapons, including models similar to those used in mass shootings. “No weapon is taken from anyone. The purpose is to dry up the supply of these weapons over time.”

Although Feinstein dropped the idea of requiring owners of semi-automatic firearms to register them, her proposal quickly drew criticism from the National Rifle Association and its allies in Congress.

“Sen. Feinstein has been trying to ban guns from law-abiding citizens for decades,” the NRA said in a statement. “It’s disappointing but not surprising that she is once again focused on curtailing the Constitution instead of prosecuting criminals or fixing our broken mental health system. The American people know gun bans do not work and we are confident Congress will reject Sen. Feinstein’s wrongheaded approach.”