Earlier this month, Rasmussen had former two-term Governor Jerry Brown edging Republican Meg Whitman, 43/41, with neither candidate showing much momentum.  In less than a month, Rasmussen shows a ten-point move by Whitman and a potentially commanding lead, while Brown appears to be fading.  With leaners, the news gets even worse for Brown:

The tie is broken for now, with Republican Meg Whitman, coming off last weekend’s state GOP Convention, moving out to her best showing yet in the race to be the next governor of California.

The latest Rasmussen Reports telephone survey of Likely Voters in California finds Whitman earning 48% support, while Democrat Jerry Brown picks up 40% of the vote. Six percent (6%) prefer some other candidate in the race, and six percent (6%) are undecided. …

Early this month, Brown was slightly ahead 43% to 41% in a contest that has been neck and neck since last September. Brown, currently the state’s attorney general, bounced briefly ahead immediately following the state Democratic Convention in April, but the race tightened again in June after Whitman’s Republican primary win.

Being from California, I can attest to the fact that a state convention isn’t going to give a candidate a ten-point bounce.  It’s good mainly for some earned media, but the candidates get chosen in primary contests in the Golden State, not conventions.  Since the primary took place in June, the Republican convention last weekend was mainly aimed at organizing, and not the kind of candidate boosting that grabs headlines and moves polls.

The trajectory of this race looks like an enhanced version of the Senate race between incumbent Barbara Boxer and Carly Fiorina.  Both Boxer and Brown are lifelong public-sector figures, the face of California’s political establishment — and with the California economy looking as grim as it is, voters there will be inclined to look for new faces.  That’s particularly true of Jerry Brown, who already served two terms in the office he now seeks from 1974-82 and helped create the regulatory regimes that are now strangling California’s economy.

Whitman is helped by two factors in the partisan split: extraordinary party loyalty from the GOP and independents breaking away from Brown.  Whitman holds 90% of Republicans (93% with leaners), while Brown only holds 76% of Democrats.  Among firm voters, Whitman has a ten-point lead among unaffiliated voters (44/34), and with leaners an eleven-point lead (50/39).  The leaners put Whitman into a majority at 51%, while Brown still trails by eight at 43% — a bad number for a man who has won statewide office repeatedly in California.

If Whitman picks up real momentum, it will help Carly Fiorina, especially if Whitman’s money gets out the vote in November.  Running two retreads at the top of the ballot may prove fatal for Democrats in this cycle.