Joe Biden opens 9-point lead over President Trump in Michigan, Detroit News/WDIV-TV poll finds

Democratic presidential candidate Joe Biden's lead in Michigan over President Donald Trump has grown to 9 percentage points, according to a poll by The Detroit News and WDIV-TV.

Biden led Trump 48% to 39% in the poll of 600 likely voters, who were surveyed over the four days following the Sept. 29 presidential debate in Cleveland, the first of three planned meetings of the major party nominees for president.

The poll detected significant shifts in key constituencies as mail-in voting has already begun in Michigan.

Subscribers:Details, analysis in Detroit News/WDIV poll of Michigan voters

The statewide poll, which was conducted by Lansing-based Glengariff Group via live operator interviews of likely voters in all regions of Michigan, had a margin of error of plus or minus 4 percentage points. Half of those were reached by cell phone.

The results, which represent only a snapshot of the race at the time it was taken, come 28 days before the Nov. 3 election and as absentee voting has already begun in Michigan. Trump won the state by 10,704 votes in 2016, his smallest margin of victory nationally.

Biden was ahead of Trump by 5 percentage points in Michigan in a similar poll over the first three days of September. Trump revealed he tested positive for COVID-19 on Friday as the survey was being conducted. 

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cmauger@detroitnews.com