The amount the United States allocates to protect its presidential candidates has climbed steeply, surpassing $200 million in the current fiscal year.
Candidates' use of the taxpayer-funded Secret Service has come under question in recent days. Donald Trump left the campaign trail Thursday for Scotland, but will spend the two-day trip celebrating the grand opening of a golf course that bears his name.
Secret Service spokeswoman Catherine Milhoan confirmed that presidential candidates who travel overseas while a so-called protectee of the Secret Service, as Trump is, receive protection abroad.
In an election cycle that has seen its share of arena rallies and riotous crowds, the Secret Service was allocated $203.68 million in the 2016 fiscal year for presidential candidate protection.
That number marks a sharp increase from previous years. In fiscal year 2012, when only the GOP had a competitive primary, $113 million was appropriated for presidential candidate protection. In fiscal year 2008, the last time there was no incumbent running for president, President George W. Bush requested $85 million for presidential candidates' protection — in turn, more than double what he had requested in 2004, The New York Times reported.
Trump is certainly not the first candidate to travel abroad during a campaign. In 2012, Mitt Romney traveled to London, Israel and Poland on what was widely panned as a gaffe-filled tour. Barack Obama traveled to Israel as well, in 2008. However, while Obama and Romney spent their trips meeting with political leaders and burnishing their foreign policy credentials, Trump appears to be traveling in a nonpolitical capacity. He has no meetings scheduled with government or political leaders, according to The New York Times.
Trump campaign spokeswoman Hope Hicks referred CNBC inquiries to the Secret Service.
Bernie Sanders has also been criticized for continuing to receive Secret Service protection — which can cost thousands of dollars a day — even as his campaign appears all but over.
However, former Secret Service Director Ralph Basham cautioned that there is no sure way to know what may happen to an active candidate for president, and that the price tag must be kept in perspective.
"I don't think the country wants to be in a position to make that decision based strictly on the dollars," Basham said. "It's no different from if a candidate decides to take a day off and go back home for the weekend, they're not doing anything political."
While Milhoan said the agency does not provide a cost breakdown by candidate, former Secret Service Director Mark Sullivan testified in 2008 that costs can reach around $38,000 per day for each protected candidate.
Basham, who led the agency during the 2004 presidential election, attributed the rising cost of presidential candidate protection to a number of reasons, and noted that it is hard to predict exactly how much money will be necessary when budgets are being drawn up ahead of time.
However, certain costs such as those associated with travel or the increasingly early start dates at which candidate receive protection, have steadily risen.
"Everything gets more expensive, transportation costs, housing, that sort of thing, that's just a natural growth," Basham said. "We're in a new age here and terrorism plays a role, and making sure that they've got the appropriate amount of resources and personnel to deal with that aspect of it is another unknown factor that they've got to take into consideration."
A man was recently arrested at a Trump rally in Las Vegas for allegedly trying to grab a police officer's gun and shoot the presumptive GOP nominee, a stark reminder of the potential threats candidates may face on the trail.
Of the candidates who ran for president this cycle, which saw an oversize field that included 17 Republican contenders, just four received protection, according to Milhoan: Trump, Sanders, Hillary Clinton, and Ben Carson.