(CNN) Just as Joe Biden -- and the rest of the 11 Democratic contenders -- were rounding the final turn in the fourth presidential debate on Tuesday night, a bombshell dropped.

No, not on the stage in Westerville, Ohio. All the way back in Washington, DC, where reports detailing how much each of the candidates raised, spent and most importantly have left in the bank began to land at the Federal Election Commission.

And the bombshell was this: Joe Biden, the former vice president of the United States and the 2020 Democratic front-runner from the day he entered the race officially in the spring, ended September with less than $9 million in the bank after spending more money than he raised in the previous three months.

SIREN.

Then consider this: Biden's total cash on hand is less than all of his main rivals for the Democratic nomination, including even California Sen. Kamala Harris ($10.5 million) who has dropped precipitously in polling over recent months. Vermont Sen. Bernie Sanders ($33.7 million) has more than three times more left to spend than Biden, while Massachusetts Sen. Elizabeth Warren ($25.7 million) and South Bend Mayor Pete Buttigieg ($23.4 million) have well more than double Biden's total.

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