“I’m certainly prepared for failure,” Sen. Chris Murphy, the Connecticut Democrat helping lead the talks, told CNN on Thursday. “I’ve been here enough times to know that this is probably the most politically complicated and emotionally fraught piece that Congress deals with.”

Murphy, who is part of a bipartisan group of senators working behind the scenes to respond to deadly gun-related attacks nationwide, acknowledged in an interview that any accord would have to be “incremental” in order to win at least 10 Republican votes to break a filibuster in the 50-50 Senate — even as he expressed optimism that a deal could be reached by next week.

“I’ve also heard Republicans make clear that as long as we’re not talking about doing everything at once, as long as we’re talking about more incremental but significant changes, they’re open,” said Murphy, who has been briefing President Joe Biden on the state of the talks.

Indeed, as House Democrats plan to move forward with a bill to ban so-called assault weapons, Senate Democrats are not even discussing a ban on firearms like AR-15s, the high-powered rifle used in the Texas elementary school massacre and a spate of mass shootings. They are also conceding that a bipartisan proposal to expand background checks on commercial firearm sales will have to be narrowed, even as the House passed a bill last year to mandate universal background checks on all commercial sales and private transfers as well.