There are more indicators that last month's Senate vote on expanding background checks was something of a dress rehearsal. Another vote appears to be brewing. Americans support the idea — as, apparently, do some Senators who opposed it last time.

As you may recall, the Senate failed to break a Republican-led filibuster of a key compromise on a 54-46 vote, coming six votes short. Four Democrats broke rank in that vote — Senators Baucus (MT), Begich (AK), Heitkamp (ND), and Pryor (AR). Since the vote, though, it's mostly been Republicans who have felt the heat. Polls from Public Policy Polling showed Senators Flake (AZ), Murkowski (AK), Heller (NV), and Ayotte (NH) facing harsh criticism for their votes. (Earlier this week, Ayotte was confronted by a furious parent from Newtown in a scene that received a lot of attention.)

Those Senators will likely get a do-over before too long. Joe Biden is continuing to press on gun safety. One of the sponsors of the background check compromise, Democract Joe Manchin of West Virginia, has said repeatedly he wants to give it another go. His co-sponsor, Pennsylvania's Republican Senator Pat Toomey, had expressed apathy about another vote. But yesterday he became more forceful, blaming the failure on a "politicized" Republican bloc.

The Daily Beast's Michael Tomasky thinks there's lot of space to pick up those six votes if there's another vote.

I talked with a couple of knowledgeable sources about what’s going on now. Five Republicans, I’m told, have expressed some degree of interest in the bill: Ayotte, who would appear be a near-certainty to switch her vote; Flake, also a likely; Murkowski; Dean Heller of Nevada; and Bob Corker of Tennessee. Tennessee seems like a tough state to be from when casting such a vote as a Republican, but Corker is someone who at least tries once in a while to have conversations with Democrats.

On the Democratic side, as you’ll recall, four Democrats voted against Manchin-Toomey: Begich, Heidi Heitkamp of North Dakota, Mark Pryor of Arkansas, and Max Baucus of Montana. I’m told that Begich would like to switch, just needs to figure out how he can get there. Heitkamp is a bigger question mark. Pryor is probably lost.

Heitkamp, of North Dakota, took office in January with the help of national Democrats — many of whom are furious at her gun control vote. Former White House Chief of Staff Bill Daley excoriated her in a piece in the Washington Post, demanding that Democrats withhold campaign financing from her future campaigns. (During her campaign, the top three regions making contributions were Washington, New York, and Los Angeles.)

Writing at The New York Times' Opinionator blog, Tom Edsall details the various political pressures Heitkamp — and other red-state Democrats — face on the issue. The superficial reasoning is based on political party: Democrats need to toe a middle-line in order to hold enough Republican votes. This point is made at the National Review: Why would national Democrats expect otherwise? The answer on background checks is that those voters supported the bill. The bigger factors at play last month were volume and distance. Constituents broadly support increases on background checks — but those who oppose new restrictions are voluble and, in the form of NRA lobbyists, knock on office doors in Washington.

There are signs — like the scene Ayotte faced this week — that constituents and proponents are getting louder. A new poll released by Quinnipiac University outlines the breadth and forcefulness of support for background checks — the latter of which appears to have broadened since last month's vote.

As always, support for expansions of background checks is broad. Even among Republicans, more than half of respondents in the Quinnipiac poll strongly support expanding checks. In every region of the country, in every type of community, more than three-quarters of respondents support the idea — the majority of them, adamantly.

And people are mad about the last vote. Only among Republicans is the split between those happy with the vote and those unhappy even close. Seventy-one percent of Americans didn't like the outcome — a full third indicated they were "angry" about how it turned out. Even people from homes where someone owns a gun overwhelmingly expressed a desire that the vote had turned out differently.

Nor would voters mind seeing the background check issue come up again. Those saying they either want Obama to maintain his focus on the issue or to include it as he pushes for other measures comprise more than two-thirds of the electorate. Only among Republicans is there a majority desire to set the bill aside entirely.

In short, then: The American people support the Senate addressing the issue again, and support increasing restrictions. There are signs that some Senators who wavered last time would be willing to go along — provided, one assumes, they're given a face-saving way of doing so. It's possible that the Senate could soon pass the measure after all.

And then there's the House.

Update, 6:56 p.m.: Apparently, the president agrees that the fight isn't yet over.

"This was just the first round," Obama told reporters at a joint press conference in Mexico. "I believe we'll eventually get that done. We'll keep on trying."