Donald Trump won Iowa’s six electoral votes by nearly 10 percentage points in his presidential election victory four years ago.

But a new poll in the one-time swing state indicates a tight contest between President Trump and his 2020  Democratic challenger Joe Biden.

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According to a Des Moines Register/Mediacom Iowa poll, Trump edges the former vice president and presumptive Democratic presidential nominee 44-43 percent among likely general election voters in Iowa. The president’s 1-point margin is well within the survey’s margin of error of plus or minus 3.8 percentage points.

Trump topped Biden by 10 points in the Des Moines Register’s March survey. The new poll also indicates the president’s approval rating has dropped from 50 percent in March to 45 percent now.

Then-Vice President Al Gore narrowly won Iowa in 2000, with then-President George W. Bush winning the state by a razor-thin margin in 2004. But then-Sen. Barack Obama took Iowa by nearly 10 points in 2008 and by 6 points four years later.

The new poll comes as the president trails Biden in most recent national polling as well as in many of the key general election battleground states. But there’s still four-and-a-half months to go until November’s election, which is an eternity in electoral politics.

The new survey suggests that Iowa – which was expected to be safe territory after Trump’s decisive win in 2016 – now appears to be up for grabs in 2020.

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The president’s reelection campaign seems to be taking Iowa seriously, spending roughly $400,000 to run ads in the state the past month according to the ad-tracking firm Advertising Analytics.

And while the president hasn’t been to Iowa since he held a rally in Des Moines a few days before the February presidential caucuses, Vice President Pence returns to the state on Tuesday.

The vice president – who is making his second trip to Iowa in the past five weeks – will tour Winnebago Industries in Clear Lake, Iowa, and deliver remarks to employees.

The Trump campaign - responding to the poll - spotlighted their grassroots outreach ahead of the state's presidential caucuses.

"After an unprecedented turnout at the Republican caucuses this year, we could not be more confident about the Hawkeye State in 2020. President Trump’s America First agenda ushered in an economic renaissance for Iowans," Trump campaign deputy press secretary Ken Farnaso told Fox News.

The Des Moines Register poll was conducted June 7-10, with Selzer and Co. questioning 674 likely Iowa voters using live telephone operators.