The comedian John Oliver doesn’t think the length of the American presidential campaign is funny. "I have no interest whatsoever in the 2016 election, at the start of 2015," he recently told reporters. "There’s a time and a place for that, and it’s in 2016."

Yet 19 months before Election Day, more than a dozen presidential hopefuls have made serious moves toward a run. Media coverage has followed along with equal intensity.

It hasn’t always been this way, at least not out in the open. The public process has slowly lengthened in recent decades — a product of rule changes that spurred the adoption of primaries and the competition among states for influence. The length of the campaigns has had the effect of increasing the amount of money required to participate.

It’s easy to identify the problems associated with a drawn-out campaign — boredom and a focus on the trivial, among them — but there are several benefits. For one, the process is more democratic than it used to be, with more people having a say in who becomes the nominee.

In the country’s early days, members of Congress chose the presidential nominees. By the mid-19th century, the process had moved to back-room wrangling at national party conventions, generally held in June of an election year.

It wasn’t until after World War II that presidential primary elections began to catch on, and they became a way for dark-horse candidates to prove their viability.

John F. Kennedy announced his candidacy for president on Jan. 2, 1960, 11 months before the general election. Between March 8 and June 7 of that year, only 16 states held Democratic primaries, and Kennedy entered and won seven of them. His victory in West Virginia, a predominately Protestant state, signaled to Democrats that a Catholic could have a chance in November, and delegates selected him overwhelmingly during the first ballot at the party’s convention in July. (Conventions started going later into the summer after World War II.)

The start of campaign season began to creep even earlier. A turning point came when Democrats changed their nomination rules after their tumultuous 1968 convention, encouraging more states to hold primaries.

In the 1972 cycle, Iowa moved its caucuses to January, in part because Democratic officials there needed time between precinct caucuses and their state convention in May to print paperwork on an old mimeograph machine. In 1976, the relatively unknown governor of Georgia, Jimmy Carter, gained a foothold by spending significant time early in the state. Future candidates took note.

In the late 1980s, other states began to move their primary dates earlier to gain influence, in a practice known as frontloading. Compressing the primary calendar into those early months of the year required candidates to have more resources at the ready earlier in the game. By 2008, four-fifths of the states held their primaries or caucuses in January, February or March.

Jump to the 2016 cycle, and it may even seem as if things are getting off to a slow start. Most candidates had declared by late March in 2007, yet Ted Cruz was the only 2016 hopeful to have made an official announcement by that time of the year.

But as Oliver lamented, the campaign season starts well before formal declarations. The so-called invisible primary, the period during which potential candidates court donors, recruit staff and gauge viability, began many months ago.

Although this behind-the-scenes, pre-campaign activity is not new to American politics, the nature of today’s news media means that it’s a lot more visible than it used to be, also contributing to why it feels so long.

Regardless of when you mark the start, the process — or at least the public part of it — in the United States is probably longer than in any other country. European systems are generally more party-driven, with party leaders deciding nominees instead of open elections. Many have set campaign periods, lasting a few weeks to several months, during which spending and other activities are heavily regulated. Some with parliamentary systems don’t even have a set election date — the current head of government has flexibility to call an election at his or her discretion.

In France, the official presidential campaign period lasts two weeks per election round, though candidates are out speaking and debating more than a year in advance. The process has lengthened in recent cycles as the country’s major parties have begun to conduct primary elections. In Britain, where the prime minister has traditionally chosen when to call an election, the coalition government effectively fixed the date of the next election to May 7 this year. Because candidates are subject to spending limits during the six months before an election, knowing when that period will occur has encouraged them to spend money earlier. But despite the extended process, the election doesn’t really begin in the public’s mind until the queen dissolves Parliament, five weeks before voting day.

So what are the downsides of the way we do it in the United States?

For one thing, many voters share the sense of fatigue Oliver says he feels, especially with the saturation of negative advertising. Polls conducted by the Pew Research Center during the last three presidential elections found that at least half of Americans consistently said that they would describe the presidential campaign as too long.

This campaign fatigue also extends to individual candidates. Running for president becomes a full-time job, sometimes requiring potential candidates to set aside whatever else they were doing to pursue it. In 2005, for example, Mitt Romney decided not to run for a second term as governor of Massachusetts, despite having had a successful first term by many measures. For candidates who already hold political office, campaigning and fundraising overlap significantly with the job of governing. Longer campaigns also go hand in hand with more expensive ones. Candidates have to start earlier to raise the funds necessary to compete.

But as demanding as campaigns may be, there are actually a few good things about the way our system works. Long campaigns allow candidates who are not already household names (or party insiders) to introduce themselves to the public. "No one knew who Bill Clinton was nine months before he became president," said Bruce Buchanan, a government professor at the University of Texas at Austin. The same was true of Carter in 1976. "He and his family went to Iowa and spent six months pounding on doors, on their own nickel," he said.

For those convinced that the drawbacks of the two-year slog outweigh the benefits, the national parties have provided a glimmer of hope. The Democrats and the Republicans put in new guidelines for the 2012 cycle requiring most states to wait until March to hold their nominating contests (though several states bucked the rules), and both parties voted to apply the rules in 2016.

But the first contest could still take place in January, because four states — Iowa, New Hampshire, South Carolina and Nevada — are exempt from that timeline. On Fox News last month, Reince Priebus, the chairman of the Republican National Committee, attempted to explain why those states get special treatment: "It is years and years and years of history — and that’s a debate, too," he said. "It is what it is."

Alicia Parlapiano and Larry Buchanan, New York Times