President Trump leads top Democratic candidates in Iowa matchups, Emerson poll finds

President Donald Trump is leading every top 2020 Democratic candidate in Iowa, according to a WHDH 7 News/Emerson College poll looking at hypothetical presidential election matchups in the Hawkeye State.

The poll found Trump leading former Vice President Joe Biden among registered Iowa voters 49%-45%, Sen. Bernie Sanders of Vermont 50%-43% and Sen. Elizabeth Warren of Massachusetts 50%-43%. The narrowest margin was against South Bend, Indiana, Mayor Pete Buttigieg, whom Trump led by one point, 46%-45%.

Those numbers indicate Trump has made gains in the state since the last Emerson poll in October that looked at hypothetical matchups in Iowa. That poll found Sanders narrowly ahead of Trump by two points, 51%-49%, while the president had a two-point lead over both Warren and Biden.

Trump won Iowa in 2016, defeating the Democratic nominee Hillary Clinton by nearly 10 percentage points. But Iowa has long been a swing state. Former President Barack Obama won it by comfortable margins in both 2008 and 2012.

The poll also found opposition to Trump's impeachment growing slightly in Iowa. Half of Iowa voters said they oppose Trump's impeachment, up from 48% in October, while 38% said they support it, down from 42%.

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Spencer Kimball, director of Emerson Polling said, "one potential explanation for Trump's improvement in Iowa is the Democrats’ inability to make the impeachment issue resonate more with voters as we saw a drop in both importance and support since October."

Among the Democratic primary candidates, the poll found Biden leading in the race at 23%, closely followed by Sanders at 22%. Buttigieg was third at 18%, and Warren came in fourth at 12%. Warren's result reflected a pronounced loss in support from the October poll, which found her tied with Biden for the lead at 23%.

Sen. Amy Klobuchar of Minnesota, on the other hand, made major gains, climbing from 1% in October to 10% in the new poll.

Sen. Cory Booker of New Jersey was the choice of 4% of Iowa caucus voters, and billionaire Tom Steyer was at 3%. Michael Bloomberg, Tulsi Gabbard, and Andrew Yang trailed the rest of the pack at 2% each.

The poll was conducted Dec. 7-10 and had a margin of error of plus or minus 3 percentage points.

This article originally appeared on USA TODAY: Election 2020: Trump leads all top Democrats in Iowa, poll finds