(The Upshot): The first six months of the Democratic primary have brought only one deep change: Pete Buttigieg has emerged as a well-known contender.

Everything else has been a modest shifting in support and positioning — nothing that has fundamentally altered the trajectory of a very long race.

It might not feel that way if you have followed every twist and turn. It can be easy to get caught up in the latest news and polls. At times, a surging candidate might feel unstoppable; a slumping candidate might seem doomed.

But up to this point, most of the seemingly big shifts in the race have actually been fairly small. Most candidates have seen their support bob up and down in a narrow range of a few percentage points, including the polling leader, Joe Biden, often in a predictable surge-and-decline pattern after their decisions to run for president.

None of the candidates in the middle of the pack have moved up to challenge Biden’s status as the front-runner. In fact, none of the candidates who started with less than 15% of the vote in an average of polls have, at any time, breached 15% in the poll averages.

Of the dozen or so candidates who started the year with little name recognition, only Buttigieg, the 37-year-old mayor of South Bend, Indiana, has become significantly better known to voters. In early February, 33% of registered Democrats said they had heard of him, according to Morning Consult’s daily tracking survey. This month, that number reached 73%.

Of course, just because big changes haven’t happened yet doesn’t mean they can’t. An important and decisive move could come any time, perhaps as soon as the first Democratic debates Wednesday and Thursday.

In recent cycles, the debates have been enough to bring more attention to some candidates and put them into contention. That was the case in 2012, for instance, for Herman Cain and Newt Gingrich. A few candidates, like Rick Perry or Scott Walker, stumbled in the debates and never recovered.

But more often, the debates have a far more modest effect, and it is important to have some perspective. A shift in support is likely to be fleeting, not a lasting change in the race.

You might feel that many candidates this cycle have already faltered, even if not as dramatically as Perry did with his “oops” moment. Former Rep. Beto O’Rourke of Texas or Sen. Kamala Harris of California, for instance, enjoyed initial success but have slipped back in the polls.

But sometimes even those who fall into a steep decline can recover, like John McCain in 2008. O’Rourke and Harris still possess the traits that made them intriguing to Democrats and could easily claw back, for example.

Sen. Elizabeth Warren of Massachusetts has already done something like what Harris and O’Rourke might hope to do. She struggled early on, in part because of questions about her electability and the way she handled a DNA test on her claim to Native American heritage. But she has since recovered, and more, going on to deliver a steady stream of policy proposals.

If Warren winds up advancing to the nomination, perhaps we’ll remember it the way we remember Donald Trump’s rise in 2016 or Barack Obama’s in 2008.

But for now, she is at just about 12% in an average of national polls — about the same support she had shortly after her announcement, a few points behind Bernie Sanders today and a few points higher than Buttigieg or O’Rourke at their peaks. Her level of support is less than what Walker had heading into the first Republican debate; he was out of the race less than two months later.

She and other leading candidates may have the spotlight now, but a lesser-known candidate could succeed in prying it away from them in the debates this week, joining Buttigieg in becoming a more familiar face to Americans.

This article originally appeared in The New York Times.