By Laura Smith-Spark
BBC News, Washington
The eye-popping sums raised by the 2008 US presidential contenders surely raise the question: what are they spending it on?
Spending is set to soar as the primary election season approaches
The early start to campaigning and the way the dates of the primary contests have been brought forward and closer together have certainly not helped the budget-conscious.
Whereas just nine states had voted on or before 5 February in 2004, more than half will have done so in 2008.
As a result, rather than focusing on a handful of key states, like Iowa and New Hampshire, the presidential hopefuls have had to take on offices and staff across a swathe of the US.
More than half of candidates' total spending from January to June was swallowed by nuts and bolts operational costs, says the Center for Responsive Politics (CRP), a non-partisan research group that tracks money in US politics.
The $80.6m sum includes staff salaries and benefits, along with office rent, equipment and supplies and administrative costs.
Another 24% of the total cash spent in the same period went on campaign expenses such as events, political consultants, polling and the posters and badges handed out to supporters.
Meet the voters
But spending on the media, which accounted for just 10% in the first half of 2007, is set to rocket, CRP spokesman Massie Ritsch says.
Mrs Clinton has been able to run fewer ads because she is well known
"Advertising will become the new number one expense and spending will be focused at first on the early primary states," Mr Ritsch said.
"With so many primaries so early, the question is: how much will they compete on the airwaves in these places, if they can't travel to all these states?
"Will they run their campaign essentially by TV or radio, which will be very expensive?"
Although campaign websites have enabled candidates to raise funds from individual donors more cheaply, Mr Ritsch does not see the internet replacing the need for mass advertising to reach less motivated voters.
"You have to meet them where they are, which is often watching TV at night or on their radio on the way to work," he said.
The Campaign Media Analysis Group (CMAG), a firm that tracks political advertising across local and network TV stations, radio and the internet, predicts huge spending.
Mitt Romney has aired most of his ads in Iowa and New Hampshire
"Based on an analysis of the 2004 election, we foresee ad spending eclipsing $800m on the presidential election alone," the company says in its newsletter.
As of 29 September this year, there had been some 16,265 ads in Iowa, making it the number one state for advertising so far.
CMAG says that New Mexico Governor Bill Richardson has run some 4,343 ads overall - more than Democratic rivals Hillary Clinton and John Edwards combined.
Republican Mitt Romney has aired more than 10,000 spots since late February and spent close to $8m, most of it in Iowa and New Hampshire, CMAG's founder Evan Tracey writes in his blog on Advertising Age.
Barack Obama, who is trailing Hillary Clinton in national polls but has been doing well in Iowa, has spent almost $2m on TV ads, Mr Tracey adds.
Level playing field
Some campaign finance reform groups have floated proposals to cut advertising costs as a way to help bring down spending and allow all campaigns to be publicly funded.
John Edwards has surprised some by accepting public funding
The suggestions include a system of "vouchers" which would entitle candidates to have air time paid by public funds, or free spots offered by the broadcasters under their public service obligations.
Candidates already have the option to accept public funding - which limits them to about $50m nationally for the primaries, about $21m in matching funds - but many choose not to do so because they consider it does not allow them to spend enough.
Deborah Goldberg, who heads the Democracy Programme at the Brennan Center for Justice at New York University School of Law, is among those who want to change the system.
"We would like to see candidates use public funding, so that candidates can still get their message out but don't have to be beholden to special interests to do so," she said.
"If the candidates understood that they were going to be playing on a level playing field, they would not feel that it was necessary to raise as much as they are raising now."
The amount offered under public funding would also have to increase substantially, she said, but the candidates would also benefit from not having to spend money to make money.
However, there are other groups who argue that increased public funding is not the answer because they see the accompanying caps on spending as limiting free speech.
Mike Schrimpf, of the Center for Competitive Politics, said: "We believe that if you want more people to run for office without limiting what they can say, you raise contribution limits."
In the first half of this year, candidates devoted about 8% of their total spending to fundraising.
A lack of cash threw the campaign of John McCain into disarray
One contender who has had his fingers burnt over his spending versus his ability to bring in the bucks has been Republican John McCain.
The Arizona senator was forced to shake up his campaign operation earlier this summer after his fundraising fell well short of projections.
Whether other candidates will feel the financial pinch as the pressure mounts in the months to come remains to be seen.
What is clear is that the sums of money being raised in this race are unprecedented - and that there is plenty of big spending to come.