The latest SurveyUSA poll of California found Republican Meg Whitman with a single-point lead over Democrat Jerry Brown in the race for governor, and incumbent Democratic Senator Barbara Boxer trailing Carly Fiorina in her re-election bid.

SurveyUSA (8/9-11)
Meg Whitman 44
Jerry Brown 43
Others 6
Undecided 6

Carly Fiorina 47
Barbara Boxer 42
Other 5
Undecided 5

This is a noticeable improvement for Jerry Brown since last month, the last time SurveyUSA polled the race. Back in July, Brown was losing to Whitman by seven points (Whitman 46% – Brown 39%). I suspect Brown’s improvement in the polls comes from simply starting to run ads and campaign more actively. Up until recently, because Whitman had a contested primary, she had been dominating the news and airwaves. On the other hand, Boxer has slipped slightly from last month when it was Fiorina 47 – Boxer 45.

SurveyUSA has been more pessimistic about Democrats’ chances in California than several other pollsters. The latest polls by Rasmussen, PPIC (PDF), and PPP all had Boxer with a lead over Fiorina. I suspect at least some of the difference comes from the different projections about turnout demographics this year. I suspect this year’s turnout is going to be very difficult to predict. You have fired-up conservatives, unenthusiastic Democrats, turned-off undecideds, and there is a big question of how many Obama surge voters come back to the polls in a midterm election.

This is the same poll that found Proposition 19 winning with 50 percent certain to vote yes and 40 percent certain to vote no. I feel like pointing out again that more voters have decided they are certain to vote for Prop 19 to legalize marijuana than say they are certain to vote for any of the candidates running for governor or US Senate.