South Carolina’s incumbent Republican Senator Lindsey Graham easily beat his rival Jaime Harrison, who spent a record US$108 million after donations from Democrats poured in from all over the country, according to Karl Evers-Hillstrom from the centre.

“To all the liberals in California and New York, you wasted a lot of money,” Graham said following his re-election.

To be fair, a number of billionaire donors gave to keep Graham afloat – and, according to the CRP, the vast majority of his funds also came from out of state.

Amy McGrath in Kentucky also suffered a blow in her face-off with Republican Mitch McConnell, a senator since 1985 who Democrats desperately hoped to unseat given his unwillingness to compromise.

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'The honour of a lifetime': US Senate Majority Leader, Mitch McConnell on his re-election victory

'The honour of a lifetime': US Senate Majority Leader, Mitch McConnell on his re-election victory

He recently triggered ire after pushing through the nomination of conservative judge Amy Coney Barrett to the Supreme Court just before the presidential vote.

The campaign of McGrath, a former Marine fighter pilot, burned US$88 million, the second costliest Senate run in US history.

Republicans also lost some expensive investments: donors nationwide gathered some US$10 million in a bid to thwart New York’s Alexandria Ocasio-Cortez, the 31-year-old Democratic socialist who’s amassed significant power in the House’s left flank, to the disdain of conservative rivals.

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Spending from her challenger, the 60-year-old ex-police officer John Cummings, along with her own US$17 million in fundraising made the race one of the most expensive House duels ever – but the representative known as AOC breezed back into Congress by more than 38 points.

For campaign financing experts, pricey losses confirm that money isn’t the only factor when it comes to winning elections, and can’t change the political landscape overnight.

Michael Bloomberg, one of the richest people in the world, learned the hard way during the Democratic Party primaries that money alone can’t buy him a spot in office: the former New York mayor spent US$550 million in advertising – a record for a campaign – but gained little traction with voters.

Fundraising is key to advertising campaigns and developing name recognition, but only goes so far in reversing long-entrenched political sentiment.

“If you are in an ultra-red state, your chances of winning are pretty close to zero,” said Evers-Hillstrom of the CRP.

Yet donations keep pouring in.

For Michael Malbin, a political-science professor at the State University of New York, the stark polarisation of the Donald Trump years has played a large role in motivating donors.

Anger and rejection of Trumpism on one side, an indictment of “Socialism” on the other – such factors are “strong motivators” to donate, Malbin said.

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It’s unsurprising, then, that the largest sums are concentrated on candidates like McConnell, Graham and Ocasio-Cortez, politicians who incite constituent’s passions.

But while thousands of donors contribute to high-profile battles, “90 per cent of the races in this country are underfunded on one side or the other,” Malbin said.

“Money is going … to the candidates who have so much money they don’t know what to do with it.”

The ease of donating online has also changed the game, since the Democrats launched the online platform ActBlue in 2004.

“It’s become incredibly easy, it’s the Amazon of politics,” Malbin said. “All you have to do is click.”

If one thing is clear, it’s that campaign spending is unlikely to fall any time soon in a country with few limits on financing elections.

“If we continue to be as polarised as we are, we can probably expect a lot of money to be spent,” said Evers-Hillstrom.