Trouble for John McCain in Arizona? While the 2010 AZ Senate race is a long way out (so you can't rely on these numbers too much, and they may be more indicative of his popularity/unpopularity at the moment than anything else), these numbers might be cause for some concern for the senator's camp:

Gov. Janet Napolitano remains the state's most popular elected official and would top Sen. John McCain in a matchup for his Senate seat, according to poll results released Tuesday.

The poll says that Napolitano, a Democrat, would defeat Arizona's senior U.S. senator by 11 percentage points, 47 percent to 36 percent, if the two were running for the Senate today. Seventeen percent of respondents were undecided, according to the poll of 629 Arizona voters conducted by the nonpartisan Phoenix-based Behavior Research Center.

Maybe this is an unreliable poll. Maybe McCain's popularity is at a low ebb right now. Of course, one remembers that Gov. Napolitano recently signed a workplace-enforcement immigration measure, while Sen. McCain has been most prominently identified with the "grand bargain." Could that be affecting Arizonans' opinions of the two?