And Senate leaders don't seem to want to put them in a bad position, risking the Democratic majority in the process. In an interview with a Nevada radio station, Majority Leader Harry Reid declared he didn't want to consider an assault-weapons ban and asked for a "cautious" approach to other ideas.
Begich, who expressed a similar call for caution, has also said he's "not interested" in banning assault weapons, while Johnson has proposed that states, not the federal government, devise their own legislation.
Their caution is justified. Even as national polls show public opinion on gun-control shifting since the Sandy Hook Elementary School massacre, it remains unpopular among the voters Johnson, Begich, and their four colleagues need to court over the next two years.
With the exception of North Carolina, Obama last year failed to exceed 42 percent of the vote in the states the vulnerable senators represent. The electorates are brimming with the blue-collar white men and women who voted in droves for Mitt Romney. What's more, the United Technologies/National Journal Congressional Connection Poll released last week found that 61 percent of white men prioritize Second Amendment rights over controlling gun ownership, and a 49 percent plurality of blue-collar white women agree. Yet, overall, 51 percent of registered voters surveyed don't.
Few doubt this is an issue that will move voters to the polls. Taxes and spending have dominated the conversation during Obama's first term, but rarely do numbers on a ledger carry the same resonance as something as culturally significant as the gun. "It's a symbol that a lot of [red-state] Democrats use to separate themselves from the party," says Andy Sere, a Republican political consultant. "You had Democrats using it in part because they knew guns haven't been big issues since the mid-'90s. They had a free pass to separate themselves from the party while not actually having to be a rogue on an important vote."
It's not, however, a fait accompli that all gun-control measures will be scuttled in the Senate, leaving the chamber to approve only less-controversial initiatives such as increased mental-health funding.
The red-state Democrats could also decide that public opinion on gun politics has shifted enough to the left that they don't need to break from their party and anger their base. A scaled-back package, one that includes a broadly popular provision like banning high-capacity magazine clips, could still pass. Johnson, for one, signaled he would consider backing such a measure, and the Congressional Connection Poll found that even a majority of white men would back it.
"The success of the two sides here depends on who comes off as overreaching," Sere says. "It depends if gun-control advocates come off as if they're trying to make an ideological play here based on the tragedy, or if gun-rights advocates come across as unyielding and unreasonable and not willing to take a look at some of these measures that are being discussed."