

Sen. Bernie Sanders (I-Vt.). (Patrick T. Fallon/Bloomberg)

The most surprising political news of the week so far had to be when a poll of New Hampshire Democrats showed Bernie Sanders leading Hillary Clinton 44-37, the first time any poll had the Vermont senator ahead of Clinton anywhere. There are reasons not to get too excited — it’s only one poll, and his lead was within the margin of error — but it’s undeniable that there is significant momentum in both parties behind insurgent candidacies. If history is any guide, however, they’ll inevitably fall short.

But in the meantime, as Philip Rucker reports in today’s Post, this appears to be the insurgents’ moment:

This has become the summer of the political outsider, as a cast of interlopers upend and dominate the presidential nominating process in both parties. The surging candidacies of Donald Trump and Bernie Sanders are fueled by people’s anger with the status quo and desire for authenticity in political leaders. Across the ideological spectrum, candidates are gaining traction by separating themselves from the political and economic system that many everyday Americans view as rigged against them.

We’ve seen this before: In the early stages of the primary process, long before any votes are cast, base voters are drawn to a candidate who offers something different than the more familiar and traditional contenders, a candidate who taps into a simmering dissatisfaction within the party. Some portion of the party’s voters — usually not a majority, but at this stage you don’t need a majority — get energized by the candidate, who is compelling in a way the other candidates aren’t. And eventually, usually when it comes time for actual votes to be cast, the insurgent’s support begins to fade and the nomination is taken by one of the more traditional candidates.

There are two explanations for why it plays out this way. The first is that voters do it on their own: They have a fling with someone new and exciting, but once it’s time to settle down, they choose someone who offers more stability. For example, during the 2004 Democratic race, some people put bumper stickers on their cars reading, “Dated Dean, married Kerry.”

Dean had seized on Democratic partisans’ dissatisfaction with party leaders who had knuckled under to Republicans for years, particularly on the Iraq War, when he made a triumphant speech at a party meeting, saying he had arrived to represent “the Democratic wing of the Democratic Party!” He captivated base Democrats and the media with an internet-driven campaign, but he finished a disappointing third in the Iowa caucus and was not long for the race. In cases like that, the voter-driven explanation is that after their initial fascination, partisans start thinking about things like electability and governing, and the more experienced insider candidates look like a safer alternative.

The second explanation for why insurgents fade is that it isn’t the result of a collective and spontaneous decision on voters’ part, but a consequence of the party apparatus finally having the ability to assert itself. And it’s when the voting starts that that apparatus matters. It’s one thing to get a bunch of news coverage and put together some well-attended rallies, but it’s a much more complicated task to get voters out to the polls, a task that relies on entrenched networks and institutions that are in the control of party leaders. That’s why endorsements matter in primaries: not just because they offer a signal to voters that their party is behind a particular candidate, but because the right endorsements bring with them connections and resources that make a great deal of difference on election day.

The truth is that both of these factors play a part in swinging support back from the insurgent to the traditional candidate. It’s great to be a bit of an outsider — enough so you can appear less tainted by whatever it is a particular voter finds displeasing about the system or the establishment or the way things have been going. But if you’re too much of an outsider, you won’t be able to convince party leaders, activists, and ultimately the voters that you can be trusted with the party’s nomination.

That was the case with the one insurgent candidate in the last few decades who actually won his party’s nomination: Barack Obama. In 2008 he was new and different and exciting, but he also played an extraordinarily skilled inside game, garnering the support of colleagues in the Senate, key African-American members of the House, and party activists all over the country. And it turned out that Obama and the people who worked for him outperformed Hillary Clinton’s campaign at all the things one normally expects the insider candidate to excel at, like raising money and understanding the intricacies of the Democratic delegate selection process.

As of now, there’s little reason to believe that the 2016 insurgents, whether we’re talking about Bernie Sanders or the many on the Republican side (Donald Trump, Ben Carson, Carly Fiorina) are capable of that. The Wall Street Journal reported earlier this week that Trump “has resisted investing in efforts to secure ballot access,” which is not what you do if you’re serious about having people actually vote for you. One of them might surprise us — every election is different, and this could be the exception that proves the rule. But this is the time for insurgent candidates to flourish, precisely because no one’s voting yet. Just don’t be surprised if it doesn’t last.