Super PACs supporting the 2016 presidential candidacy of former Florida Republican Governor Jeb Bush spent over $14 million on ads promoting his bid for the GOP nomination in Iowa, which only resulted in a sixth-place finish.

According to Morning Consult’s ad spending data, Bush campaign super PACs spent the most of any candidate in either party on Iowa campaign ads. On the GOP side, Sen. Rubio’s campaign and super PACs spent the second-most at almost $12 million. The campaign and super PACs backing the Republican Party’s Iowa winner Sen. Ted Cruz spent over $7 million on ads in the state, and billionaire Donald Trump netted a second-place finish by spending a little under $4 million.

The Huffington Post notes that Bush spent $2,800 per vote, which is reportedly 18 times what Cruz spent per vote. Bush’s per-vote spending was also 34 times higher than Trump’s and 10 times higher than Rubio’s.

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U.S. Senator Rand Paul, who finished in fifth place ahead of Bush, only spent a little over $2 million on Iowa ads between his campaign and its supporting super PACs.

Though Bush’s super PACs did outspend all of the other campaigns, his official campaign itself did not spend any money on Iowa ads, suggesting a lack of focus on the state by his campaign. Super PACs supporting the rest of the GOP candidates spent a combined total of a little over $17 million on the race, just over $3 million more than the political action committees supporting Bush.

Following the Supreme Court ruling in Citizens United v. FEC in which the court affirmed the right of individuals, non-profits, and corporations to spend their own money to express their political views, critics claimed that the ruling would lead to a future in which billionaires would purchase election outcomes through the use of super PACs.

While Iowa campaign data alone can not prove or disprove that theory, the results in the Republican caucuses do not appear to show any specific connection between campaign spending and vote totals.

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On the Democratic side, Hillary Clinton’s campaign and super PACs spent about $1 million more than Senator from Vermont Bernie Sanders, though Democratic super PACs only spent a total of $287,000 on the entire contest, most of which was spent by PACs supporting Martin O’Malley.

“Money can’t buy votes, apparently,” wrote The Huffington Post in its analysis of Bush’s Iowa ad spending.

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