A new poll shows that Sen. Dianne FeinsteinDianne FeinsteinFranken: Trump Jr., Manafort need to testify under oath Trump Jr., Manafort reach deal to avoid public hearing next week Senate panel subpoenas co-founder of firm tied to controversial Trump dossier MORE (Calif.) is the clear favorite in the Democratic primary for governor of California in 2010 - a race she has yet to commit to.

The Field Poll found that 38 percent of Democratic primary voters surveyed would back Feinstein. Former Gov. Jerry Brown came in second in that primary, earning 16 percent.

Among Republicans, former eBay CEO Meg Whitman holds a slight lead over former Congressman Tom Campbell and state insurance commissioner Steve Poizner. Whitman earned 21 percent among Republican respondents, while Campbell got 18 percent and Poizner 7 percent.

Feinstein led the Democratic field by a similar margin in another poll at the beginning of the month as well.