UH Poll: Clinton leads Trump by 10 in Harris County

Hillary Clinton is leading Donald Trump in Harris County, according to a UH poll. Click through to see how the candidates are doing in the Houston area. Hillary Clinton is leading Donald Trump in Harris County, according to a UH poll. Click through to see how the candidates are doing in the Houston area. Image 1 of / 8 Caption Close UH Poll: Clinton leads Trump by 10 in Harris County 1 / 8 Back to Gallery

Democratic presidential candidate Hillary Clinton has a comfortable 10-point lead over her Republican rival, Donald Trump, among registered voters in Harris County, according to a new poll released Thursday.

The survey from the University of Houston’s Hobby School of Public Affairs showed Clinton winning 42 percent support to Trump’s 32 percent. Nine percent of respondents said they back Gary Johnson, the Libertarian Party candidate, while 2 percent said they support Green Party candidate Jill Stein.

About 15 percent said they were undecided, according to the poll.

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Should Clinton carry the county with a double-digit margin, it would mark the widest margin of victory for a Democratic candidate in Harris County since 1964. Harris County, the third largest in the nation, long has been a competitive county during presidential election years. In 2012, President Barack Obama beat Republican challenger Mitt Romney there by nearly 600 votes. Obama edged out GOP nominee John McCain in 2008 by just under 2 percentage points, 50.4 percent to 48.8 percent.

“The results suggest that the outcome of the presidential contest in Harris County, as well as the results of dozens of down-ballot contests, could hinge heavily on the level of voter enthusiasm and turnout,” said Jim Granato, professor and executive director of the Hobby School of Public Affairs.

When the poll considered only likely voters, Clinton's lead slipped to 9 percentage points. In the survey's pool of extremely likely voters, though, the race is firmly within the margin of error, with Clinton at 43 percent and Trump at 39 percent.

Trump's high unpopularity numbers show no signs of hurting down-ballot Republican candidates in local races, the poll found. Harris County District Attorney Devon Anderson, a Republican, has a razor-thin edge over her Democratic opponent, Kim Ogg, 30 percent to 29 percent. In the race for county sheriff, Republican Ron Hickman leads Democrat Ed Gonzalez by a 6-point margin, 36 percent to 30 percent.

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However, the poll showed that a plurality of respondents were unsure about their choice for both offices – 47 percent for district attorney and 36 percent for sheriff.

"Neither party can depend on presidential coattails or incumbency, frequent mainstays of politics," said Renée Cross, associate director and researcher at the Hobby School. "With only six weeks to go, the county candidates have a lot of work to do in this highly unpredictable election."

The poll was based on 550 telephone interviews and was conducted Sept. 1-20. The margin of error is plus/minus 4 percent.