The still-very-crowded Democratic presidential primary has been polled pretty extensively this year, giving observers a sense of who’s doing well in their efforts to win over likely Democratic primary voters and caucusgoers and who is having a hard time gaining traction. And the polls have been shifting gradually over the last few months: Former Vice President Joe Biden retains his first-place standing while Sen. Elizabeth Warren continues to make slow and steady progress, and Sen. Bernie Sanders has slipped somewhat, although he has maintained support in the mid-teens for some time.

But despite many months of campaigning, there still isn’t a clear party consensus — there’s a clear top tier of candidates, but no runaway leader has emerged. So in a field this large, we have turned to asking people who they don’t want the Democratic nominee to be. One of us (Masket) has been doing this as part of his early-state activist interviews since April, and the other (Peterson) included this question in a recent survey he conducted with Iowa State University/Civiqs among likely Iowa Democratic caucusgoers. (Peterson is planning to ask the question again in followup surveys.) To be sure, our approaches measure different things — the preferences of a few dozen party activists aren’t necessarily the same as those of several hundred caucus goers — but we have found some similar patterns.

For starters, one of the most notable features of this primary field is just how many people don’t want to see Sanders as the nominee even though he’s currently third in the national polls. Obviously Sanders is backed by an enthusiastic set of supporters, but we’ve also found that he has a substantial number of detractors in the party. In Masket’s August early-state activist interviews, 59 percent of activists (17 of 29 people interviewed) said they did not want him to be the nominee (compared with 21 percent — 6 people — who said they were considering supporting him); only Miramar, Florida, Mayor Wayne Messam and Rep. Tulsi Gabbard earned worse marks (62 percent — 18 people — did not want either of them to be the nominee). Meanwhile, in that Iowa State University/Civiqs poll, 25 percent said they didn’t want to see Sanders as the nominee (compared with 16 percent who listed him as their first choice), giving him the second-worst marks of any candidate on this question.

The suggestion here is that Sanders is a factional candidate; a specific set of Democrats are very excited about him, but he has limited ability to expand that coalition into a broader base of support. For instance, in that Iowa State University/Civiqs poll, Sanders has struggled to win over new supporters — among those who didn’t back him in 2016, less than 1 percent want to see him become the nominee in 2020, and a third specifically do not want to see him nominated. Of course, that doesn’t mean Sanders cannot win the nomination — President Trump was arguably a factional candidate for much of the 2016 cycle — but it does mean Sanders’s potential for growth is limited.

Another candidate with a substantial number of detractors is … Biden. That’s right, even though he still sits near the top of the polls, he was the No. 1 candidate who likely Democratic voters said they did not want to see as the nominee (30 percent) in that Iowa State University/Civiqs poll. Likewise, in Masket’s August early-state activist survey, 31 percent (9 people) of those interviewed said they did not want to see Biden become the nominee. Granted, this was not anywhere close to the percentages who said they didn’t want Messam, Gabbard, or Sanders nominated, but it was still quite high given how many activists also said they were still considering Biden (34 percent, or 10 people).

It may be harder to think of Biden as a factional candidate than Sanders, given that Biden also enjoys significant support among a broad swath of demographic groups within the party, including a majority of African American voters. But he’s nonetheless facing a situation in which, if he did win, he might be a relatively controversial nominee who alienates some wings of the party or has trouble generating enthusiasm that can translate into voter turnout.

To be clear, this doesn’t mean Sanders and Biden are actively disliked by the party; both of them actually have high favorability ratings — 73 percent and 72 percent of Democrats had favorable opinions of Biden and Sanders, according to an average of national August polls by FiveThirtyEight’s Nathaniel Rakich. And if you look at Iowa surveys that also ask this question, Democrats have a fairly favorable view of both Biden and Sanders. But our question is different — we’re not asking whether respondents like a candidate; we’re asking who they don’t want to win the nomination. And while that question might capture some candidates who people dislike, it’s also entirely plausible that many Democrats like Biden and Sanders but still don’t want them to be the nominee.

Of course, it’s also plausible that Biden and Sanders experience more opposition than the other candidates because people simply know more about them — they both have high name recognition and long histories in politics. We found that candidates without such histories, like Warren and former Housing and Urban Development Secretary Julián Castro, weren’t really opposed yet by early-state activists or Iowa caucusgoers. This could change, though, as Warren’s new status as a front-runner means a good deal of criticism and media attention will be aimed at her, and the number of Democrats uncomfortable with her as the nominee may well rise.

One other thing to keep in mind is that it’s not entirely clear how strong this opposition to Biden or Sanders actually is. And that’s because this is a comparison among other Democratic candidates — and not a comparison to, say, Trump. Democrats care a lot about winning this year, so if either Sanders or Biden were to win the nomination, Democratic activists and voters who don’t want to see them as the nominee may still rally behind them. But it makes sense that the party would want a nominee who can speak to all of its key constituencies, or at least not alienate many of them. So as Democrats look to find a candidate who can not only keep the party together but also keep the party’s supporters enthusiastic about voting in 2020, they can’t afford to ignore the fact that some potential nominees are disliked by a substantial portion of the party.