Over the weekend, the Rocky Mountain Poll released a survey showing Barack Obama leading Mitt Romney in Arizona, 44 percent to 42 percent:

The state's two most populous counties, Maricopa and Pima, came out in support of Obama, while Romney has a lead in the rural counties. Men are evenly split between the two candidates, and the difference between the candidates among women is only three points.

Obama is the heavy favorite among the state's Latinos, who split for him 77% to Romney's 10%.

This doesn't sound even remotely plausible to The Range. Nate Silver crunches the numbers and is also skeptical:

The survey has a couple of things in its favor. The poll comes from a firm, the Behavior Research Center, that has had good results in the past. And almost all of its interviews postdated the Denver debate.

But I would not be too worried about the topline numbers if I were Mr. Romney’s campaign — or too enthralled with them if I were Mr. Obama’s. The survey contacted relatively few respondents — about 500 voters — and even a good polling firm can and will produce an outlying result or two with a sample size like that.

It is plausible that Mr. Obama could win Arizona if he is running strongly nationwide — but it is much less likely that he will do so in the current national environment, where the race is almost tied.

We're not even sure that you can say that Behavior Research Center has had good results in the past. Having watched the outfit for years, we find it to be hit and miss, at best.

But Silver raises an interesting point regarding Hispanic voters:

On Saturday, I ran an alternate version of the FiveThirtyEight simulation in which I assumed that Mr. Obama would in fact win Hispanic voters by 50 percentage points, his edge in the Latino Decisions poll, as opposed to the roughly 35-point margin he’s had on average in polls that were conducted in English only.

I scaled this adjustment based on the share of Hispanic voters in 2008 exit polls. So, for example, Mr. Obama gained a net of 3 points in Texas because of the adjustment, but almost nothing in Kentucky.

Even with this adjustment, Mr. Obama was far from being favored in Arizona. Instead, the model gave him just an 8 percent chance of winning there, although this was better than the 4 percent chance from the standard FiveThirtyEight model.

However, the adjustment increased Mr. Obama’s win probability in Colorado to 57 percent from 44 percent, in Florida to 53 percent from 35 percent, and in Nevada to 77 percent from 62 percent. It even helped him slightly in Virginia, where about 5 percent of voters identified as Hispanic in 2008 exit polls.

He concludes:

Still it’s the possibility that the polls are underestimating Mr. Obama’s performance among Hispanics that should be the concern for Mr. Romney in the Arizona poll — not the unlikely possibility that Arizona has suddenly become a swing state.