There are a bunch of polls circulating around about whom Americans are going to blame if and when the federal government shuts down. Here's Pew, and here's NBC/WSJ, and here's Quinnipiac. They all say pretty much the same thing, that the public is evenly split on whose fault it will be. We should take them all with a big grain of salt, and here's why.
First, most people haven't given much thought to a government shutdown yet. It's always good to remind yourself that most Americans don't pay much attention to politics, particularly compared to the kind of political junkie you are if you read this blog. They may have heard that the parties are fighting about the budget, but chances are that when the pollster asks them who will be to blame if the government shuts down, it's the first time they've considered it. So their opinions are unformed, and thus subject to change.
Second -- and this is the important point -- the shutdown will be a dynamic, ongoing story for as long as it lasts. It isn't like a vase dropping off a table, and then we stand around and say, "Whose fault was that?" It will dominate the news for days, maybe weeks. There will be extended reporting and discussion and debate. There will be events within the story. At some point, someone will say something stupid, which the other side will make noise about. Both parties will attempt to have their preferred narrative about its causes and effects prevail. Consequently, how people think about it and whom they blame will be the affected deeply by the evolution of that debate.
So asking Americans now whom they'll blame if a shutdown happens is like asking people whom they think is going to win the next round of American Idol. It can tell you a bit about the context in which the shutdown will begin, but it doesn't tell you much at all about what the outcome is going to be, either in practical terms or in terms of how Americans are going to think about it afterward.