Actually the ' serious" candidates have to ask for SS protection.
John Mccain didn't ask for it in 2000.
There are so many whackos out there it makes sense to provide it for the serious contenders.
Interesting info from a slate article
"Only viable, moneyed contenders need apply, so Dennis Kucinich and Al Sharpton will likely have to watch their own backs during this election cycle. A candidate must first request protection from the Secret Service, a move that some politicians hesitate to make because it cramps their style. John McCain, for example, never asked for a security detail during his 2000 presidential run, fearing that black-suited goons would discourage him from pressing palms with plain folks and making impromptu campaign stops. And in 1992, Ross Perot delighted in pointing out that he hadn't enlisted the Secret Service's aid, half-jokingly telling supporters that he didn't need any bodyguards because "everybody loves me."
Once a request is filed, the Secret Service then reviews the candidate's financial and electoral status to see whether he or she qualifies. The guidelines stipulate that, in order to receive protection, a candidate must enjoy "national prominence," receive 10 percent or more of the vote in two consecutive primaries or caucuses, and qualify for federal matching funds in excess of $100,000. In lieu of the matching funds criteria, a candidate can also qualify by having raised more than $2 million in contributions. Lastly, the candidate must be running for a party that received at least 10 percent of the popular vote in the previous election, which disqualifies the likes of Libertarian front-runners Michael Barnarik and Gary Nolan. (As a result, it's not clear that Perot would even have been eligible for protection in '92.) The rules change a bit after April 1, when candidates can qualify for protection by virtue of having received 10 percent of his or her party's committed delegates."
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