Former Florida governor Jeb Bush announced to supporters in South Carolina that he was suspending his presidential campaign after a disappointing performance in the state's GOP primary. (AP)

This post has been corrected.

Campaigns are expensive. That's the whole deal, right? It's the reason candidates wring their hands over the financing process while they make donor calls on their Bluetooth headsets. It's why Bernie Sanders and Donald Trump have done so well, railing against the big-money donors as Sanders cobbles together a nest egg from spare change and Trump assembles his from the checks he never got around to cashing.

But raising a ton of money is not a guarantee of success, as Jeb Bush (and his massive super PAC) can attest. Bush spent a ton of money to finish sixth, fourth and fourth in the first three Republican contests. While Trump, who enjoys the ability to get media coverage every time he opens his mouth, spent relatively little.

Bush is not the extreme, however, even among the six candidates left by the time voting in South Carolina rolled around. Looking at money spent by the campaigns through the end of January 2016 — the most recent data available — the candidate spending the most per vote was Ben Carson.

Ben Carson is blowing a ton of money on his doomed campaign, much of which is going back out to the fundraisers. It's a reminder that how campaigns spend money matters as much as how much they spend.

Notice, too, that this excludes money spent by super PACs. If we included the $100 million-plus spent by Bush's, Right to Rise, he'd be far and away the winner on most-spent-per-vote. But that waste of cash isn't his fault, and let's face it: Guy is already having a bad 24 hours.

Correction: Due to a calculating error, this article originally excluded votes accrued in South Carolina in the money-per-vote calculus, which is obviously a big mistake. The figures have been corrected. I apologize for the error.