At midnight Tuesday the residents of tiny Dixville Notch, N.H., will welcome camera crews for the quadrennial ritual of casting the first votes in the nation's first presidential primary.

The remote town near the Canadian border is so small that it has only a roomful of registered voters and zero racial diversity. Its votes in recent cycles have been unreliable indicators of who will win the primary.

But the cameras will be there, nonetheless, because it is first, and because it is a tradition.

Dixville, in its quaint way, is just the New Hampshire primary writ small — or in this case, smaller. You have to wonder why it gets so much attention. But the answer of course is that it is first, and the other answer is that it has been first for a long long time.

So long, in fact, that many of us have simply become fond of it all. As Daniel Webster famously said of New Hampshire's Dartmouth College: "Yes, it is a small school, but there are those of us who love it."

New Hampshire started loving it back in 1916, which makes this the 100th anniversary. But don't expect to hear that proclaimed from the rooftops in New Hampshire. It's no secret of course, and it is readily acknowledged. But there is also a certain sense of New England reticence about it.

Perhaps this is because so many other states have long envied this first-in-the-nation status. More to the point, other states have long coveted the political clout, media attention and economic injection that accompany that status.

And every now and then one state or another takes a serious run at displacing the Granite State. Not in this cycle, as it happens, but there is no sense in waking a sleeping dog.

Why did New Hampshire decide back in 1916 that it should have a presidential primary? The idea was a product of the progressive movement of the turn of the century. In states such as Wisconsin, where progressive Republican administrations were in flower, primaries were established for state office. In 1910, Oregon added a presidential primary to direct the votes of its delegates at the next nominating conventions.

By the election of 1912, a dozen states were using primaries either to choose delegates or to express a presidential preference. New Hampshire was part of a subsequent surge that raised the number of primaries to a score by 1920.

The wrinkle New Hampshire added was the idea of having a primary very early, before anyone else. This was a gamble. Most primaries accompanied the spring thaw or the approach of summer. Would candidates even countenance the idea of traipsing through the snow? It turned out that quite a few would.

New Hampshire started having its primary in March. Since then of course, as other states encroached with ever-earlier events, New Hampshire has gone as early as January 8. And state law requires that the event be held at least a week before "any similar vote" in another state.

When the first primaries began, presidential candidates were chosen at national conventions of the major parties, much as they are now. But the delegates to those conventions were not chosen by popular vote or open caucuses.

Instead, the delegate slots were filled by each party's officeholders and other officials, power brokers and other inside players. This allowed the state party leaders to hold their state's votes as a bloc and deliver them at the convention, often in exchange for pledges of one kind or another from the candidates.

That remained the case for most states until the 1970s. But primaries and caucuses grew in popularity in the decades after World War II. And as the media coverage of presidential campaigns expanded to include not only newspapers and magazines but radio and television and the digital world, the demand for reportable events and metrics grew exponentially.

The first state to really feel this postwar shift was good old New Hampshire with its first-in-the-nation status. The state had reformed its ballot access in 1949 to generate more participation in the quadrennial event, and sure enough, the people came out in 1952 and the people shook things up.

That year's primary put a torpedo in the hull of incumbent Harry S. Truman, who was serving his elected term as president after serving nearly all of Franklin D. Roosevelt's fourth term. Truman was still undecided about formally seeking a second term in his own right, but after New Hampshire voted for Estes Kefauver, a senator from Tennessee, Truman decided not to run.

On the Republican side that year, the fix was thought to be in for the party's Senate leader, Robert A. Taft of Ohio, the son of President William H. Taft. But the voters preferred the war hero general Dwight Eisenhower, and that trend would continue to the convention that summer.

That established the state as a giant killer, of sorts, and there have been other memorable moments of truth. Many recall that President Lyndon B. Johnson was humbled by the New Hampshire results in 1968. While LBJ won that primary, a peace candidate named Eugene McCarthy attracted a youthful army of supporters and got 42 percent of the vote. Within a few weeks, Johnson had announced he would not run for re-election.

New Hampshire has long prided itself not only on its iconoclastic tendencies but on its prescience about presidential timber. Until 1992, every elected president in both parties since 1916 had won the New Hampshire primary along the way.

Even the breaking of that skein by Bill Clinton had an asterisk, because Clinton finished a surprisingly strong second in New Hampshire that year to popular Sen. Paul Tsongas of neighboring Massachusetts. Doing so enabled Clinton to call himself "the comeback kid."

Since then the state's reputation for picking the president has been battered, as neither of Clinton's successors won here. George W. Bush lost badly in 2000 to John McCain, and Barack Obama fell to Hillary Clinton in 2008.

But as the primary celebrates its centennial this year, its role and importance in the presidential nominating process is as great as ever — perhaps greater.

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