The 2020 primaries kicked off on Monday, with both Democratic and Republican caucuses held in Iowa.
Up for grabs are 41 delegates for Democratic contenders and 40 delegates for the Republicans.
With 100% of precincts reporting, former South Bend, Indiana, Mayor Pete Buttiegieg and Sen. Bernie Sanders were both leading among Democrats at 26%.
President Donald Trump handily won on the Republican side with more than 97% of the vote.
For the Democrats, a strong finish across the Hawkeye state's 99 counties could establish an early lead for one hopeful, separating that candidate from a crowded pack.
During the last presidential cycle, Texas Sen. Ted Cruz won the 2016 Iowa GOP caucuses with then-candidate Trump finishing second.
On the Democratic side, former Secretary of State Hillary Clinton prevailed over Sanders.
For complete elections information, visit the ABC News elections home.