Welcome to FiveThirtyEight’s weekly politics chat. The transcript below has been lightly edited.

sarahf (Sarah Frostenson, politics editor): For the first time this cycle, fewer than 10 candidates qualified for Thursday night’s debate. Under the DNC’s tougher criteria (4 percent support in at least four national or early-state polls or 6 percent support in at least two early-state polls, plus 200,000 unique donors), just seven candidates made the cut: Joe Biden, Pete Buttigieg, Amy Klobuchar, Bernie Sanders, Tom Steyer, Elizabeth Warren and Andrew Yang.

What does that mean for tonight’s debate? Are there really only seven viable candidates at this point? (There are still 15 “major” candidates running, according to FiveThirtyEight’s definition.) Fewer than seven?

nrakich (Nathaniel Rakich, elections analyst): In my opinion, the candidates who meet the DNC’s standards and the candidates whom voters are seriously considering are pretty divorced from each other.

And the latter list has been in flux all year (and may continue to be in flux through the early-state primaries).

Right now, it seems pretty clear that Biden, Sanders, Warren and Buttigieg are the most serious contenders. Earlier this year, though, that list would have been Biden, Sanders, Warren and Kamala Harris (after the first debate) or just Biden and Warren (for much of the fall).

sarahf: But you’re not arguing that candidates who didn’t make the stage are still being seriously considered, Nathaniel? Or are you?

nrakich: No, definitely not.

But I do think the DNC has two choices when it comes to debates at this stage: either 1) aim for a small debate among just the serious contenders, in which case the standards for qualification should be stricter, or 2) open the debate to all major candidates until the voting actually starts to happen.

This seven-candidate debate is neither. So it’s kinda frustrating.

geoffrey.skelley (Geoffrey Skelley, elections analyst): Yeah, the DNC is in a tough position. Cory Booker and Julián Castro have both criticized the DNC for its debate qualification criteria, and Booker even sent a letter calling on the DNC to include candidates who had hit either the donor threshold or the polling threshold. I’m not sure it would solve the problem Nathaniel is outlining, but under Booker’s suggestion, Booker, Castro and Tulsi Gabbard would have all qualified.

sarahf: But is the field really so in flux that more candidates on the stage would help voters decide?

perry (Perry Bacon Jr., senior writer): A lot of Democratic voters said they are still making up their minds — 34 percent in a recent Huff Post/YouGov survey, compared to 48 percent who said they had a “good idea” of who they are voting for. So I don’t think voters are totally set yet. But I think there is a media effect here, too. Only a few candidates (Buttigieg, Warren, Biden, Sanders) are getting a lot of coverage, so I think it’s hard for voters to see other candidates as viable, but that’s in part because the DNC and the media have written off the rest of the field.

ameliatd (Amelia Thomson-DeVeaux, senior writer): It seems like increasingly we’re in a situation, as Nathaniel mentioned, where there are four main contenders and the rest of the candidates are pretty much indistinguishable in terms of their support. That does make the stakes higher for Klobuchar, Steyer and Yang since they aren’t doing as well in the polls and could benefit from the spotlight tonight.

But on the other hand, many of the lower-tier candidates have had good debates (Booker, for example) and it hasn’t really made a difference for them.

nrakich: Right, we’re at the point where voters have had plenty of exposure to candidates like Booker, and they’re just not that interested.

geoffrey.skelley: But with just seven candidates, there’s a chance Klobuchar, Steyer and Yang could all get a bit more time to make their case tonight. And that could make a difference, particularly for Steyer and Yang, who spoke the fewest words in the last debate.

perry: Klobuchar has lucked out in that she is the only candidate on tonight’s stage with traditional credentials, outside the top four. (Harris would have fit in this group as well, but she’s dropped out.) Now I don’t think this necessarily means Klobuchar will pick up support, but she is the most logical person for people to go to next if they have concerns about the top four.

geoffrey.skelley: And conveniently for Klobuchar, her strongest early state is Iowa, the first state to vote. So an uptick in her numbers after the debate could pay dividends right at the start of voting.

nrakich: She does seem like the candidate most likely to go on a Carter- or Clinton-esque tear based on a strong early-state performance. But Carter and Clinton have historically been the exception, not the rule.

sarahf: What’s been so surprising to me in watching the debates is just how much the “middle tier” has struggled to break out. Arguably, Buttigieg and Klobuchar have had the most success in this regard, but as you can see from our latest poll with Ipsos there is a real disparity among the top four candidates — Biden, Warren, Sanders and Buttigieg — and everyone else.

Never say never, but it seems so unlikely that this overall picture dramatically shifts tonight.

perry: Looking back on this process, I think I have to either rethink what I consider a good debate performance (I have always thought Klobuchar and Booker did well and yet, they often went nowhere) or rethink whether debates matter much (in my view, Biden has been bad in several of the debates, yet that has not hurt him much).

ameliatd: It just seems like the issue isn’t so much that voters dislike the Klobuchars and Bookers of the race — they just have options they like more. So Klobuchar doesn’t just need a good debate performance — she needs some of her rivals to stumble. And that’s the tricky thing to predict here.

perry: That’s well put.

So by that logic, she really needs Buttigieg to be bad, right?

ameliatd: I do think of the top four contenders, the stakes are highest tonight for Buttigieg and Warren.

sarahf: Why Warren, Amelia?

ameliatd: She’s had the slip in the polls, and voters I’ve talked with seem pretty concerned about her health care plan. She didn’t really get a chance in the last debate to defend her plan — maybe you’d call that an escape — but it’s not great if people are looking for reassurance. So if there are questions about health care tonight, that could be an opportunity for Warren to do some reframing. On the campaign trail, for instance, she’s been talking more about voters having a “choice” with health care, perhaps in response to concerns about Medicare for All getting rid of private insurance.

sarahf: And what about the “Bernie is Back narrative” … any nibblers?

geoffrey.skelley: No, at least not yet.

For every national poll that has Sanders at 22 percent, there’s another with him at 16 percent. We shouldn’t write off Sanders, and it’s possible that his polling numbers are ticking up slightly, but to characterize it as “Sanders Surges” is misleading.

nrakich: Sanders is where he’s always been — hovering around 15 percent!

It’s just that, with Warren’s support several points lower than it was this fall, Sanders’s 15 percent (well, 18 percent according to our tracker) is good for second place now instead of third.

perry: I do think the stakes are high for Sanders tonight, though. Buttigieg and Biden will probably try to cast him as the crazy liberal tonight as much as they will Warren — or maybe even more, considering she has plunged so far down in the polls.

Warren has been attacking Buttigieg and Biden more directly on the campaign trail, so it will be interesting to watch for that as well. I tend to think this is a mistake for her, because Buttigieg is good at counterpunching and the moderators so far have been deeply invested in the “Democrats have moved too far to the left” narrative so she has that working against her, too.

nrakich: Hm, Perry, I disagree that Buttigieg and Biden should train their fire on Sanders. Buttigieg still needs to gain more ground in order to become a serious threat for the nomination, so he might want to continue chipping away at Warren’s support. And I think Biden might like having Sanders in a strong position; after all, Biden was in a much more precarious position when Warren had consolidated much of the liberal vote.

ameliatd: I tend to think Buttigieg will go after Warren simply because she’s been going after him. That back-and-forth has taken kind of a personal tinge — both of them are attacking each other’s corporate backgrounds/connections. But it can be riskier for a female candidate to go on the attack because of gender stereotypes about how women should present themselves. Not to say Warren can’t thread that needle, but it’s another layer of difficulty for her to navigate.

geoffrey.skelley: One plus for Warren is that she regularly scores well in debates. In October and November, she had the strongest rating (or was tied for it) in our polling with Ipsos.

nrakich: Yeah, Geoffrey, but she also fell in the polls right after the November debate, so that didn’t necessarily matter.

geoffrey.skelley: Sure, but she could use this debate to shift the conversation toward something more appealing to voters — say, her plan for a wealth tax — which polls significantly better than Medicare for All.

ameliatd: She has been pivoting pretty explicitly to it on the campaign trail. And as Geoffrey mentioned, that makes sense given it’s quite popular. It also helps that it’s her signature policy. But Booker also attacked it in the last debate, saying it’s “cumbersome” and pointing out that wealth taxes failed in other countries. Granted, he won’t be on stage tonight, but I wonder if Buttigieg might attack it, too.

sarahf: The Warren vs. Buttigieg conflict you all are highlighting is interesting, because even though they’re pretty different ideologically, they pretty much appeal to the same types of voters (college-educated whites). The catch, of course, and maybe one reason they should focus on attacking other candidates, is they both need a way more diverse base of support to have a serious chance at winning the nomination.

perry: Buttigieg’s lack of support from black voters has become one of the biggest narratives of the campaign. And I think it’s what I’m most interested in ahead of this debate. How do the moderators ask him about this? What do the other candidates say, since none of them are black? Does Biden, the person with all the black support, attack Buttigieg on these grounds? And most importantly, how does Buttigieg respond?

It’s not just how black voters think about this either. When I talk to white voters who like Buttigeig, they’ll say something like, “What is the deal with black people and Pete?” I think this is a real barrier for him.

ameliatd: Yeah, I think that will be really interesting to watch, Perry. I’ve also heard that concern about Buttigieg from white voters. Interestingly, not as much about Warren, even though she is also struggling somewhat among voters of color.

sarahf: This piece from The Washington Post earlier this week offered a pretty sympathetic portrayal of some of Buttigieg’s issues with winning over black voters. So part of me wonders whether he will be able to talk a bit more candidly tonight about reaching black voters or if he sticks to more rehearsed, well-trodden talking points. For instance, in that article it talked a lot about Buttigieg coming to terms (or at least thinking about) his own white privilege, and I think he could maybe have some powerful moments on what white privilege means if he chose to move in that direction.

perry: Pete’s problem right now isn’t with black voters as much as it is with white voters who need reassurance that he is good on racial issues with black people. The best way for him to win black voters is probably to win Iowa and New Hampshire. But as for these next two months, I’m not sure I know what he should do. His comments in that Post piece were kind of weird, like he was studying black people.

ameliatd: Talking about privilege is a hard thing for the white candidates to do, too. I remember when Kirsten Gillibrand said in an early debate that she could explain white privilege to white women in the suburbs — and it fell kind of flat. It’s just a challenge for white candidates to do in a way that seems genuine and unrehearsed.

sarahf: I thought that, too, in reading the piece, Perry. He’s treating it like a problem he has to fix … which is probably a very white way of thinking about things.

ameliatd: It feels very on-brand for Buttigieg, too, which I think is part of the problem. The consultant’s approach to fixing your standing with voters of color.

perry: There is a small cohort of young black people who are more liberal and who support Sanders or Warren. But the issue for Buttigieg is that the older, more moderate voters he attracts tend to be white, while the older, moderate black voters tend to be very pro-Biden. And I don’t think any of that changes in the short-term. So I feel like Buttigieg is kind of stuck. If I were him, I would talk about electability if I were trying to boost my black vote numbers.

geoffrey.skelley: It’s hard to make the case that you’re electable if the most votes you’ve ever captured in an election you won is 11,000.

perry: Yes, but it’s better than talking about white privilege, I think.

My other somewhat related question is, Yang made it to the debate, which means we don’t have to have a discussion about why there are no minority candidates. But do we think that discussion happens anyway? Do the other candidates have to pretend to be sad that Harris, Booker and Castro aren’t there? (It’s a competition, those people lost.)

nrakich: I am sure they will pay lip service to Booker and Castro. It is a competition, but it helps in a competition to appear like a gracious winner!

Also, if Booker and Castro are on the brink of dropping out, their endorsements could soon be in play.

perry: I found the whole narrative around Harris leaving the race to be odd — that somehow this is a big void because there are not enough prominent minority candidates. The concerns of black and brown voters are not being ignored. I can’t remember a field that has talked about racial issues more.

ameliatd: I think candidates like Warren are probably genuinely not happy with the fact that Steyer is on the stage and Booker isn’t. On the campaign trail, Warren has been attacking unnamed billionaires (cough cough, Bloomberg) for trying to buy their way into the race. So I wonder if lamenting the absence of Booker/Castro can also be a way to go after Steyer.

geoffrey.skelley: The question is, of course, whether it’s worth attacking Steyer, who doesn’t have much obvious space to move upward in the race.

nrakich: That’s smart, Amelia. Something like, “I’m running against a system where it’s easier for a billionaire candidate to get a public platform than it is for a black candidate.”

perry: That would be a good argument.

I am sad Bloomberg won’t be there because Warren and Sanders seem to really dislike him and I think the feeling is mutual.

ameliatd: Steyer is a less appealing billionaire punching bag, imho.

sarahf: So we’ve talked about how tonight could be crucial for Warren and Buttigieg, which makes sense considering they’re both a bit behind Biden and Sanders and need to close the gap. (In our national polling average, she’s at almost 15 percent and Buttigieg is at 10 percent. Biden, on the other hand, is in the lead by a fairly healthy margin — 27 percent — with Sanders in second at 18 percent.)

But couldn’t Biden also do something tonight to help solidify his support? That’s just as crucial a question, right?

nrakich: It is an important question, but I’m not sure his performance will matter much. We’ve seen him struggle in past debates without suffering any real polling consequences. I guess if he has a really strong performance, it could help him? But honestly, I feel like he’d have to have a few strong performances in a row in order to really convince people, “OK, yeah, this guy has it together.”

ameliatd: Biden has yet to have a really stellar debate performance. I wonder what would happen if he managed to have a gaffe-free night and stayed consistently on point until the very end. Maybe nothing? But maybe it would allay some voters’ concerns.

geoffrey.skelley: A “Biden Dominates Debate” kind of headline would certainly mark a big change of pace.

ameliatd: But does the debate really have the potential to help Biden surge? This is on the same night the new Star Wars movie opens, after all.

nrakich: Yeah, Amelia, plus the holidays are coming up … I bet this will be the least-watched debate so far.

ameliatd: On the other hand, I was in Iowa this past weekend and talked to a not-insignificant number of voters who are just starting to tune into the process. So even though I remain a skeptic about the impact of the debates, I think it’s important for us tired journalists to remember not all voters have been watching since June.

perry: One question I have is whether this is all just a 2016 replay? The candidate with the support of non-college voters in his party gets a steady lead, watches the other candidates attack each other and just wins? (This is how Trump won the 2016 GOP primary.) I’m struggling to see Biden losing — or gaining — much support from this debate until some of the candidates drop out after Iowa and New Hampshire. Like the one thing we know so far about his numbers is they are just really stable, right?

geoffrey.skelley: Right, but the state-by-state nature of the actual primary process is something we can’t forget about. Biden may be leading in the national polls right now, and will likely be leading them when Iowa votes on Feb. 3, at least at the current rate. But we don’t know how voters will react if Biden loses a couple contests coming out of the gate.

So even if the debate isn’t all that impactful, that doesn’t mean this race is over by any means.

nrakich: I do think the January and February debates will be more impactful, for the reason Amelia says. People in New Hampshire will watch the New Hampshire debate that happens four days before they vote and is aired on their local news station, for instance.

perry: The particulars of what happens the next few months are important, yes. But right now, I am having a hard time seeing anything other than a gradual march toward a Biden victory.

geoffrey.skelley: I guess I’m leaving the door open for other changes. We’ve seen candidates have late surges in Iowa before — Rick Santorum in 2012 or John Edwards and John Kerry in 2004.

But Biden’s strength among black voters is absolutely a key factor, and none of the other candidates on stage — or Bloomberg, for that matter — have a record of appealing to that part of the Democratic base. So if no one else can make serious inroads with African American Democrats, it may be difficult to beat Biden for the nomination.