2020 United States presidential election in Iowa

The 2020 United States presidential election in Iowa was held on Tuesday, November 3, 2020, as part of the 2020 United States elections in which all 50 states plus the District of Columbia participated. Iowa voters chose electors to represent them in the Electoral College via a popular vote, pitting the Republican Party's nominee, incumbent President Donald Trump of Florida, and running mate Vice President Mike Pence of Indiana against Democratic Party nominee, former Vice President Joe Biden of Delaware, and his running mate California Senator Kamala Harris. Iowa has six electoral votes in the Electoral College.
Trump won the state 53.1% to 44.9%. Prior to this election, most news organizations had considered Iowa as either leaning towards Trump or a tossup. As was the case in Ohio, this election has confirmed Iowa's trend from a Midwestern swing state toward the GOP column, à la neighboring Missouri starting in 2008. Iowa had voted Democratic in six of seven elections prior to 2016, with the exception being George W. Bush's narrow plurality win in 2004. In 2016, however, Iowa voted for Trump by an unexpectedly large margin of 9.4%, voting over ten points to the right of the nation overall, indicating a possible realignment of the previously Democratic-leaning state towards the GOP, much as in the case of West Virginia in 2000 and 2004. Even though Biden contested the state, Trump ended up carrying it by an only slightly reduced margin of 8.15% even as his national margin of defeat grew by 2.4%, confirming this trend. 
Biden became the first Democratic nominee since Jimmy Carter in 1976 to win the presidency without carrying Iowa, as well as the first since FDR in 1940 to win the presidency without carrying Dubuque County. Biden improved on Hillary Clinton's margins in the Des Moines and Cedar Rapids metropolitan areas and traditionally conservative western Iowa, the latter which borders Nebraska's 2nd congressional district (Omaha urban area), an electoral vote Trump won in 2016 but lost in 2020. Trump improved on his 2016 performance in populist northeast and south Iowa. 
Per exit polling by the Associated Press, Trump's strength in Iowa came from White people with no college degree, who comprised 62% of the electorate and supported Trump by 58%–40%. Trump also dominated amongst White Christian voters, garnering 66% of Protestants, 54% of Catholics, and 76% of born-again/Evangelical Christians. 53% of voters believed Trump was better able to handle international trade. Trump continued to win the cultural message among voters without college degrees in the Hawkeye State.
During the primary season, there remained hope among Democrats that Iowa would still be a contestable state. However, Trump's well-held victory in the state in the general election also saw Republican congressional candidates -- from Senator Joni Ernst to two House seats, both held by Democrats (one vacated by Dave Loebsack in Iowa's 2nd district) -- winning their election.
Neither Biden nor Trump flipped any counties in the state, although Biden came within 2% of flipping Dallas County, a suburb of Des Moines. 
Iowa is one of three states that voted twice for Barack Obama and Trump, the other two being Ohio and Florida. This was also the first time since 2000 when Iowa did not back the overall winner of the electoral college, and presidency.
Caucuses.
The state's caucuses, traditionally the first major electoral event in the country, were held on February 3, 2020.
Republican caucuses.
Incumbent president Donald Trump received about 97 percent of the votes in the Republican caucuses, and received 39 of the GOP delegates, while Bill Weld received enough votes to clinch 1 delegate.
Democratic caucuses.
After a three-day delay in votes being reported, the Iowa Democratic Party declared that Pete Buttigieg had narrowly won the state delegate equivalent (SDE) count of the Democratic caucuses with 26.2 percent. Bernie Sanders came in second with 26.1 percent of the SDEs, despite the fact that he received more popular votes (26.5 percent) than Buttigieg (25.1 percent). Elizabeth Warren, Joe Biden, and Amy Klobuchar finished in third, fourth, and fifth place, respectively.
Libertarian caucuses.
The Libertarian Party of Iowa conducted their own caucuses on February 8, offering in-person caucus locations and an online virtual caucus. Only registered Libertarian voters were eligible to participate.
General election.
Polling.
Graphical summary
Aggregate polls
Polls