If it was exclusively up to Golden State voters, Barack Obama could go ahead exchange his title of senator for president right now, the results of a Field Poll released on Wednesday show.

The survey shows that the Democratic ticket of Barack Obama and Joe Biden leads the Republican ticket of John McCain and Sarah Palin by a 52 percent to 36 percent margin. The 16 percent point lead remains significant but is down from the 24 point lead the Democratic team enjoyed in July. An aggregate 3 percent of voters prefer other candidates, while 9 percent remain undecided.

The poll also shows that California remains a mostly "purple" state in the way Republcan-Democratic voters are geographically distributed.

Voters residing in California's coastal counties, who represent 70 percent of the state's likely electorate, prefer Obama-Biden over McCain-Palin overwhelmingly, 57 percent to 32 percent. Conversely, those voters in the state's inland counties favor the Republican ticket 46 percent to 38 percent, the survey showed.

The poll was based on a survey of 830 likely voters and was conducted between Sept. 5 -14. The poll has a margin of error of plus or minus 3.5 percent.