As Scots head to the polls Thursday to decide the fate of their country, the voters will be weighing a number of economic factors, among others. And while the UK advertising industry has a stake in the outcome, some firms will have cashed in on the referendum vote -- win or lose.

M&C Saatchi, the advertising agency founded by brothers Maurice Saatchi and Charles Saatchi after they were ousted from their own Saatchi & Saatchi in the early 1980s, was hired in June to help the Better Together (No) campaign in the final 100 days. No figures were released on how much the campaign’s advertising Hail Mary cost, nor how much Blue State Digital – an agency hired by Better Together in 2012 -- was paid by Better Together. A spokesperson from Blue State Digital who spoke with International Business Times declined to disclose the amount Better Together paid them.

But based on the amount of campaign donations raised, Better Together and the pro-independence campaign Yes Scotland are estimated to have spent well in excess of 4.5 million pounds ($7.4 million) combined to convince voters which way they should mark their ballots.

According to the Electoral Commission, an independent body that regulates political parties and election finances in the UK, a total of 2.7 million pounds ($4.4 million) was raised by Better Together and 1.8 million pounds ($2.9 million) was raised by Yes Scotland. And these figures reflect only the sums raised during the reporting period from Dec. 18, 2013, to Sept. 5, 2014. The campaigns began fundraising after they launched: Yes Scotland in May 2012 and Better Together in June 2012.

During that time between December 18, 2013 to September 5, 2014, both campaigns had to report all individual donations exceeding 7,500 pounds ($12,280). In the 16 weeks leading up to polling day, both sides were limited to spending 1.5 million pounds ($2.5 million) apiece. All of these provisions were established by the Scottish Independence Referendum Act – a measure passed by Parliament that set limits on campaign donations and spending, among other regulations that outlined how a referendum would take place.

Both campaigns have received millions from high-profile donors. "Harry Potter" creator J.K. Rowling donated 1 million pounds ($1.6 million) to Better Together. Crime fiction writer Christopher Sansom donated 200,000 pounds  ($328,000). Rain Dance Investments, the holding company of hotel and distiller tycoon Donald Houston, also donated £200,000 to the pro-union movement.

A large chunk of Yes Scotland’s cash has been donated by Chris and Colin Weir, a Scottish couple who won a lottery jackpot of 161 million pounds ($264 million) in 2011. They made two donations – one for 1 million pounds ($1.6 million) and another for 2.5 million pounds ($4.1 million), the Herald reports. Other notable donors include former Scottish National Party candidate Randall Foggie, who donated 125,000 pounds ($205,000) and Elizabeth Topping, the wife of Ralph Topping, the former chief executive of online betting bookmaker William Hill, donated 50,000 pounds ($82,000) to Yes Scotland.

Notably absent from the donor’s list – on both sides – are businesses. According to the Wall Street Journal, companies are reluctant to donate over fears of public backlash. Rowling faced an onslaught of criticism after she made her Better Together donation. On Twitter, she became the target of online abuse where she was labeled a "traitor", "whore" and "specky b******," the Huffington Post reported. Police were asked to investigate allegations of “online criminality” after a charity sent an offensive tweet.

Yes Scotland employed the marketing agency Cor Agency --  a firm that had worked on successful Scottish National Party campaigns in the past -- to create its marketing strategy for the organization’s launch.

In September 2012, Ian Dommett, the director of Cor Agency, became the director of marketing of the Yes campaign, he told International Business Times. He left Yes Scotland in January along with Stan Blackley, deputy director of communities. According to Dommett, since his departure a freelance team comprised of Will Atkinson and Jim Downie have been working on the Yes Scotland marketing campaign. Dommett did not disclose how much Yes Scotland paid Cor, nor any details of the campaign’s marketing budget. But based on their reported spending, the budget was significant.

In February, Yes Scotland unveiled a 2.5 million-pound ($4.1 million) outdoor advertising campaign – with ads to appear on billboards, posters and phone booths across the country. An unnamed industry insider who spoke to The Telegraph said the campaign would be "one of the biggest Scottish outdoor advertising campaigns ever," adding that Yes Scotland is believed to have raised  7 million pounds ($11.5 million) to put toward marketing. If that figure is correct, it illustrates indeed how far in excess of the recorded donations the campaigns raised. IBTimes was unable to identify specifically which agencies and vendors were paid as part of the multi-milliion dollar campaign.

Notably, a Guardian story last published last week outlined the concerns of  M&C Saatchi and other top advertising agencies in London, who fear the repercussions of a Yes vote on the industry in general and their Scotland-based clients. “It cannot be a good thing,” M&C Saatchi chief executive David Kershaw told the Guardian. “Creating potentially a customs wall between what was a united market cannot be good for trade or for brands. Disruption to clients is what is worrying.”

Potential loss for their clients notwithstanding, in the event that profits thin out in the near future, it appears M&C Saatchi might have created a cushion for itself with its referendum campaign work.

M&C Saatchi and the Better Together campaign have no reason to be confident that the vote will go their way. And neither should the Yes Scotland supporters: It's simply too close to call. The historic vote is unprecedented in myriad ways; among them, it’s the first UK vote with a voting age of 16, for one.

Both campaigns have targeted the younger demographic through social media, with each enlisting celebrities to advocate their position, PR Week reports. According to research from the University of Glasgow, research on both campaign’s Twitter accounts show that Yes Scotland followers were more active than Better Together’s. As of Thursday, Yes Scotland had 104,000 Twitter followers. Better Together had 42,400.

While polls in January showed an estimated 60 percent of Scottish voters favored the pro-union side – today the No campaign holds a with a mere 52-48 lead over the "Yes" campaign, within the margin of error, a recent YouGov poll suggests.  

Voters will be able to cast their vote until 10 p.m. local time (5 p.m. EDT) on Thursday. Results are expected to start coming in at 2 a.m. But Scotland's largest cities including Glasgow, Edinburgh and Aberdeen may not report results until after 5 a.m., Reuters reports.