(CNN) Bernie Sanders served notice to the rest of the 2020 presidential field when his campaign announced that he raised $5.9 million in its first 24 hours of existence. That's million of dollars more than he raised in the first 24 hours of his 2016 bid and millions more than any of his Democratic competitors have so far announced.

But what does Sanders' impressive haul signal for his chances of winning the nomination? It's a good thing: primary winners do tend to lead in early fundraising. That said, history suggests that fundraising doesn't tell us much in forecasting primary winners once we account for early polling.

Put simply: when fundraising tells one story and early polling tells another about who is most likely to win the nomination, early polling is more likely to be predictive.

I went back and looked at every open nomination process since 1980 to look at how well primary winners raised money in the early going. Specifically, I examined whether or not they led in fundraising during the half or full quarter after they registered their candidacy with the FEC . (Note: we're using quarterly FEC reports because most candidates have historically not publicized first day fundraising. Also, I excluded 1992 because eventual nominee Bill Clinton didn't register with the FEC until the second half of 1991 of the 1992 cycle, and I wanted to know how much explanatory power early fundraising truly has.)

The majority of candidates who won their parties nomination led the field in early fundraising . This includes Walter Mondale in 1984, George H.W. Bush in 1988, Michael Dukakis in 1988, Bob Dole in 1996, George W. Bush in 2000, Al Gore in 2000, Mitt Romney in 2012 and Hillary Clinton in 2016. A number of them did not, however: Ronald Reagan in 1980, John Kerry in 2004, John McCain in 2008, Barack Obama in 2008 and Donald Trump in 2016.

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