September 21, 2012, 5:00 PM GMT+0

Republican challenger Mitt Romney leads Democratic President Barack Obama by ten percentage points in Arizona, 51% Romney to 41% Obama, in a poll of 674 registered voters statewide, conducted by YouGov.

In Arizona:

Partisan loyalty is strong on both sides, as 91% of Democrats are sticking with Obama and 92% of Republicans are voting for Romney.

Independents split in Romney’s favor, 54%-35%.

Men favor Romney by 58%-33%, while women favor Obama by 48%-44%.

Obama leads in Pima County-Tucson (50%-37%).

Romney leads in Maricopa County-Phoenix (51%-41%) and in the rest of the state (60%-33%).

The oldest voters age 65+ favor Romney (69%-29%). The youngest under age 30 favor Obama (60%-30%).

Republican Jeff Flake leads Democrat Richard Carmona, 43%-37%, in the race to fill the seat of retiring Senate Republican Whip Jon Kyl. Many (20%) are still undecided.

Voters in Arizona favor Republicans in the vote for U.S. House, 42% Republican-34% Democrat with 25% not sure. The poll was conducted online September 7-14, 2012.

Sampling method: Respondents were selected from YouGov’s panel using sample matching. A random sample (stratified by age, gender, race, education, and region) was selected from the 2005–2007 American Community Study. Voter registration, turnout, religion, news interest, minor party identification, and non-placement on an ideology scale, were imputed from the 2008 Current Population Survey Registration and Voting supplement and the Pew Religion in American Life Survey. Matching respondents were selected from the YouGov panel, an opt-in Internet panel.

Weighting: The sample was weighted using propensity scores based on age, gender, race, education, news interest, voter registration, and non-placement on an ideology scale.

Number of respondents: 674 registered voters statewide.

Margin of error + 4.7% (adjusted for weighting).

Click here for a complete report of results