LOS ANGELES (Reuters) - Democratic U.S. Senator Barbara Boxer of California has opened up an 8 percentage point lead over Republican challenger Carly Fiorina as she picks up a greater share of independent voters, a Field Poll showed on Friday.
Boxer, considered one of the most liberal U.S. senators, has gradually broadened her lead over the conservative former Hewlett-Packard CEO after holding a 6 percentage point advantage in September and a 3 percentage point lead in July, according to the poll.
A three-term senator facing her toughest re-election fight, Boxer now has 49 percent of the vote to political newcomer Fiorina's 41 percent, according to the final Field poll released ahead of the November 2 election. Another 6 percent were undecided.
Non-partisan voters favor Boxer over Fiorina 49 percent to 32 percent in the survey of 1,501 registered voters between October 14-26.
Returning Boxer to Washington is crucial for Democrats, now in the majority, as they face a loss of U.S. Senate seats amid voter frustration over jobs and a sluggish economic recovery.
In reliably Democratic California, Boxer is polling strongly in the more liberal Los Angeles Country and the San Francisco Bay Area, where they favor her two to one or better over Fiorina.
Fiorina -- who was hospitalized overnight this week for an infection but is back on the campaign trail -- has a stronger showing in the Central Valley and areas of Southern California outside Los Angeles.
Female voters prefer Boxer 51 percent to 36 percent for Fiorina, while male voters narrowly support Boxer 47 percent to 44 percent.
Reporting by Mary Milliken; Editing by Dan Whitcomb and Jerry Norton