DES MOINES, Iowa – For nearly a half-century, the Iowa caucuses have kicked off the presidential nominating calendar.

And while their record of picking presidents is inconsistent, the winner of the caucuses has gone on to win their party’s nomination more than half the time.

2020 PRIMER: HOW THE IOWA CAUCUSES WORK

Only three caucus winners – Democrats Jimmy Carter in 1976, Barack Obama in 2008 and Republican George W. Bush in 2000 – went on to win the White House.

But the caucus winners have a better batting average when it comes to winning the presidential nomination – at least on the Democrats' side.

Seven of 10 Democratic caucus winners have gone on to become their party’s standard-bearer. Just three winners of the eight contested GOP caucuses eventually won the Republican nomination.

Here’s a look at the past winners, starting with the 1976 contests – when both major political parties held presidential caucuses.

1976

Democrats: Former Georgia Gov. Jimmy Carter

Republicans: President Gerald Ford

1980

Democrats: President Jimmy Carter

Republicans: Former congressman and former CIA director George H.W. Bush

1984

Democrats: Former Vice President Walter Mondale

Republicans: President Ronald Reagan (unopposed)

1988

Democrats: Rep. Richard Gephardt of Missouri

Republicans: Sen. Bob Dole of Kansas

1992

Democrats: Sen. Tom Harkin of Iowa

Republicans: President George H.W. Bush (unopposed)

1996

Democrats: President Bill Clinton

Republicans: Sen. Bob Dole of Kansas

2000

Democrats: Vice President Al Gore

Republicans: Texas Gov. George W. Bush

2004

Democrats: Sen. John Kerry of Massachusetts

Republicans: President George W. Bush (unopposed)

2008

Democrats: Sen. Barack Obama of Illinois

Republicans: Former Arkansas Gov. Mike Huckabee

2012

Democrats: President Barack Obama

Republicans: Former Sen. Rick Santorum of Pennsylvania

2016

Democrats: Former Secretary of State Hillary Clinton

Republicans: Sen. Ted Cruz of Texas