Nevada, more than any other state, symbolizes how much the Presidential race has changed over the last six months.
Mitt Romney, on the other hand, polled much better with voters in Nevada than he did in most of the rest of the country. His favorability on our last poll there was narrowly positive at 45/44, and he managed to tie Obama at 46% in a state where the President won by 12 points in 2008. PPP's other polls in the state in 2011 showed a similarly close Obama/Romney race- a 1 point lead for Obama in July, a 3 point lead for Romney in April, and a 1 point lead for Obama in January.
That's not the case anymore. Over the last 5 months Obama's approval numbers have recovered, Romney's favorability numbers have taken a strong turn in the wrong direction, and Obama's opened up an 8 point lead in the state at 51-43.
Obama's 44/53 approval rating in the state has now flipped to positive territory at 50/46. Most notably what was a 42/53 breakdown with independents is now 55/40. He's seen smaller improvements with Democrats (from a 78% approval rating to 82%) and with Republicans (from a 6% approval to 12%).
Romney's net favorability meanwhile has dropped by 14 points to -13 with 38% of voters seeing him positively to 51% with a negative opinion. Part of his strength in Nevada had been an unusual number of Democrats seeing him favorably, but that crossover appeal has dropped from 27% to 18%. With independents his favorability is 36/54.
Adding Brian Sandoval to his ticket wouldn't do a lot to help Romney win Nevada.
With Hispanics choosing Sandoval as his Vice President still leaves Romney down 64-33 to Obama, although that's a modest improvement from 69-30 in the straight Obama/Romney question. Sandoval could be a good running mate for Romney for other reasons, but flipping Nevada to the GOP column doesn't look to be one of them.
The Republican who comes closest to Obama in Nevada is actually Ron Paul, who trails 49-42. Rick Santorum and Newt Gingrich trail by 54-40 and 54-39 respectively.
Obama's not out of the woods in Nevada. His numbers there are still weaker than in 2008, and Romney could certainly see some recovery once he's the GOP nominee. But things are looking a lot better for the President there than they did over the course of 2011.
Full results here