Sen. Bernie Sanders (I-Vt.) walks though the crowd during the Capitol City Pride festival in Des Moines, in June. (Christopher Smith for the Washington Post)

Back in 2016, Sen. Bernie Sanders’s near miss in the Iowa caucuses served as a launchpad for a long, inspired challenge to Hillary Clinton. Despite losing the state by less than a point, many news outlets declared him the effective winner.

Ahead of the 2020 caucuses, though, Sanders (I-Vt.) appears to be in considerably rougher shape in the Hawkeye State. According to new polling, he’s in the single digits, his image has taken a hit, and even some of his 2016 supporters may not be considering him.

The Monmouth University poll is the second since the first Democratic presidential primary debate to show him dropping into the single digits in Iowa. At 9 percent, he trails former vice president Joe Biden (28 percent), Sen. Elizabeth Warren (19) and Sen. Kamala D. Harris (11) — albeit within the margin of error against Harris.

Sanders did fare significantly better in a third recent Iowa poll, though, taking 19 percent in a CBS News/YouGov survey a few weeks ago, and his national polling has also been relatively stable after dropping earlier in the summer. Monmouth’s poll also includes a slightly older sample than showed up for the 2016 caucuses, which might depress the numbers of a candidate like Sanders, who does so well with younger voters. So it’s worth waiting to see if more quality Iowa polling shows a similar decline. (It’s also possible Iowa voters are tuning in earlier than other voters, given they hold the first contest, and don’t mirror the nation as a whole.)

But if the new poll is close to accurate, it’s not a great omen. As with the Suffolk University poll a month ago that also put Sanders at 9 percent, this one shows relatively few Iowa voters have him as either their first or second choice. In this poll, another 8 percent name Sanders as their second choice, meaning he’s the first or second choice of just 17 percent of voters. That’s compared to 40 percent for Biden and 38 percent for Warren.

As I argued last month, this is especially ominous for Sanders given he took nearly 50 percent of the vote in the state in 2016. He was never going to get that much of the vote again, given this is a crowded field instead of a two-candidate field, but he’d probably hope to at least be a leading option for lots of voters early in the process. In both this new poll and the Suffolk poll, he’s either tied or trailing South Bend, Ind., Mayor Pete Buttigieg on first- and second-choice voters.

In addition, even that CBS/YouGov Iowa poll that was better for Sanders showed fewer Iowans said they were considering caucusing for him (40 percent) than said they were considering caucusing for Warren (55 percent), Harris (53) and Biden (50).

The Monmouth poll also shows Sanders’s image declining considerably. His favorable rating dropped from 67 percent in April to 58 percent today, while his unfavorable rating rose from 26 percent to 33 percent — the highest in the field. His +25 split between his favorable rating and his unfavorable rating is a far cry from where it was on the eve of the 2016 caucuses, when Monmouth put it at +76 (85/9). (And even if Monmouth’s sampling might be off, that trendline doesn’t look great for Sanders.)

Sanders is hardly sunk in the 2016 race; the Iowa State Fair just began, for crying out loud, and his national polling has him hanging tough with Warren behind Biden. The New Hampshire primary, which he won by 22 points in 2016, will also give him a good shot at a victory in the first two states. But Iowa plays a huge role in this process, and if these polls come close to presaging the eventual result for Sanders, that would be a very tough early verdict for the 2016 runner-up.