Erosion takes time. With news that the Senate might push a vote on a package of new gun legislation for another week, opponents gain seven more days to wear down support for its elements — even for some of the more popular elements, like new trafficking regulations.

There are four components to the Senate package: increased funding for school safety programs, new gun trafficking penalties, increased background checks, and a ban on assault weapons. They're listed in the order of how likely they are to pass, from most to least. The NRA's goal is to pull the entire package to the right until it crosses the invisible line of 40 votes needed to tank the entire thing — or until what remains up for approval is sufficiently watered-down. They've done so with the fourth element, the assault weapons ban, already. It's well past the 40-vote line, and as a result will be voted on as an amendment to the main package. That will fail.

Then the NRA ramped up opposition to the next least likely, background checks, tugging at it steadily. It was already tottering on the boundary, after a bipartisan effort to reach compromise on its provisions failed. The organization stumbled a bit on this issue yesterday, when former Senator Asa Hutchinson, the NRA's point person on its new school safety plan, told CNN that he was open to expanded background checks. The Huffington Post reports:

"You can do it within a way that does not infringe upon an individual, and make it hard for an individual to transfer to a friend or a neighbor or somebody... and have a casual sale," Hutchinson said. "We don't want to infringe upon those rights, either."

While Hutchinson's comments express support for background checks, he stopped far short of endorsing the type of universal background checks for all gun sales that have been proposed in Senate legislation.

The NRA quickly clarified Hutchinson's comments. "He meant expanding it to include more people into the national instant check system," the lobbying group said in a statement to CNN.

But it didn't really matter. Even had there been a defector in its ranks, the NRA was likely to win on background checks, too. Senate Majority Leader Reid postponed a vote on the package until after the Senate's recess in the hopes that a compromise could be reached in the interim. There's no sign that a compromise — which would focus on assuaging Republican concerns that expended checks might lead to a national gun registry — is within reach.

So the NRA moves down the line. The newest target for the NRA is the generally popular effort to increase penalties for illegally trafficking firearms. Senate Bill 54 would expand regulations on "straw purchases," purchases made for resale to someone not eligible to own a weapon. While never a slam dunk (it passed the Senate Judiciary Committee on an 11-7 vote, with Sen. Grassley of Iowa providing the sole Republican vote), it's generally been seen as a common-sense step.

For the NRA, it's still too much. The Hill reports:

The bill as written would penalize anyone who purchases a gun for someone prohibited from owning it or for someone intending to use it in a crime.

The NRA argues this language could penalize people unfairly.

If a person buys a gun and sells it to another person, who in turn sells it to yet another person, the bill’s language could be used to punish the initial buyer of the gun, the NRA says.

The gun lobby also wants to cut a measure that would see someone convicted of straw purchases surrendering any weapons and ammunition in their possession, though in most analagous situations — like the illegal sale of prescription drugs — confiscation would be the norm.

Grassley is already wavering.

“I voted for the trafficking bill in the Judiciary Committee, but it was far from a perfect piece of legislation,” Grassley said.“At the time, I explained that there were changes that needed to be made before I would support it on the floor.”

There will now be more time for any such changes. The Times reports that votes on the package likely won't happen until the week of the 15th — in part because Reid still hopes to reach a compromise on background checks. Maybe he can. The White House seems optimistic that the package will pass, and President Obama will stump for gun control reform today in Colorado.

But that week also gives the NRA more time to keep pulling the package to the right, to see what it can get across that 40-vote line. And to make sure that whatever's left on the other side for approval contains only provisions the group find palatable.