SAN FRANCISCO (CBS SF) – With 40 days until Election Day, a KPIX 5 / SurveyUSA poll finds Hillary Clinton increasing her lead over Donald Trump among California voters. Meanwhile, the senate race between Kamala Harris and Loretta Sanchez has tightened.

The poll taken after Monday’s debate found Clinton leading Trump among likely voters by a margin of 59 percent to 33 percent.

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Adding third party candidates, Libertarian Party candidate Gary Johnson has 3 percent support and Green Party candidate Dr. Jill Stein has 2 percent. Three percent of likely voters surveyed are undecided.

A SurveyUSA poll taken earlier this month found support for the Democratic nominee is up 2 points, while the Republican nominee’s support is up 1 point.

Clinton has a 35-point lead support among women in California. Latino voters are backing Clinton by a 50-point margin, and the Democratic nominee is leading African-American voters by 71 points.

The survey found Trump has a 4-point lead among rural voters, evangelical voters (4 points) and California gun owners (5 points).

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The poll found 71 percent of Clinton voters are enthusiastic about their candidate, while 64 percent of Trump voters are enthusiastic.

While Clinton appears very likely to win California’s 55 electoral votes in the presidential race, the battle to replace Sen. Barbara Boxer is apparently narrowing.

SurveyUSA found Attorney Gen. Kamala Harris is leading Rep. Loretta Sanchez of Orange County by a margin of 40 percent to 29 percent. Compared to a poll 3 weeks ago, support for Harris has dropped 4 points, while support for Sanchez has gone up 2 points.

Pollsters found nearly one-third of voters surveyed were still undecided between the two Democrats. No Republican candidate received enough votes in the June primary to advance.

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SurveyUSA interviewed 900 California adults for the survey. The margin of error is plus / minus 3.5 percent.