Now that the 2020 Democratic field is pretty much set (barring a last minute Stacey Abrams or John Kerry bid) with former Vice President Joe Biden getting in Thursday, let's look at what we've learned so far about the field and what to watch for going forward:

1. How far does name identification go? Biden is a huge boulder in the lake, and his entry into the presidential campaign is sending ripples throughout the primary field. So far, he leads the pack. That's largely a product of the fact that people know the former vice president and recognize his name.

It's true that there are plenty of recent examples of candidates who led early and faded – Jeb (!) Bush in 2016, Hillary Clinton and Rudy Giuliani in 2008, and before that, Jerry Brown in 1992 and Gary Hart in 1988. But there are also others who led from pretty much the start and won the nomination, even if in a long slugfest – Hillary Clinton in 2016, Mitt Romney in 2012, Al Gore and George W. Bush in 2000, for example.

2. It's there for Biden now, but can he prove himself? The crowded field that's trending left gives Biden an opportunity. So much of it will depend on Biden's ability to do four things — remain disciplined, answer critics fully, raise money and show he has the stamina to win. One advantage he does have, though, is that the Democratic base still likes Joe Biden. Horse-race polling is ephemeral, but how people feel about the candidates is less fleeting. And Biden also leads the field in favorability ratings – an average of 74 percent of Democratic voters say they like him, while just 15 percent say they don't.

3. Can Bernie Sanders expand beyond his loyal base? So far, the Vermont senator has shown he's going to be a force in the Democratic primary and will likely have the funds to be there for the long haul. Money, for him, isn't going to be a worry the way it will be for Biden. We know who Sanders' constituency is; they like him, and it's deeply rooted. The question remains: Can the self-avowed democratic socialist (the only candidate of the 20 running comfortable identifying with the "S" word) move beyond that base and prove to the other pragmatic Democratic voters that he can beat Donald Trump — the one thing they really seem to want.

4. Does Pete Buttigieg continue his momentum? The 37-year-old South Bend, Ind., mayor has seen a star turn. Since arriving on the national scene, Pete Buttigieg has impressed many in the base with his versatility, calm and confident demeanor, and his vision. That's led to an increase in name ID, a steep rise in favorability ratings and... money.

He has a thin campaign organization that isn't yet built for the long haul – and he's still not as well known as many of the others in the race. While he's well liked among the party faithful with an average of 42% positive, 8% negative, that means half still don't have an opinion or don't know who he is. He's going to have to staff up and continue to bring in the cash so he can meet as many voters as possible to get better known, especially now as the field became a little more smooshed.

5. Does Elizabeth Warren find her lane? The Massachusetts senator only has so much time to find her lane. Warren is credited by many as having the most detailed plans and some of the most well thought-out ideas. But she's lagged in fundraising and in the polls, and that's hard to sustain with the kind of heavy campaign operation she's built, paying out, for example, $1.2 million for salaried staffers.

She's a strong debater and the strength of her ideas may break through in a debate, but she's fighting with others in the progressive and grassroots space. It's probably partially why Warren stood apart from the Democratic field in calling for President Trump's impeachment immediately following the partially redacted Mueller report's release. And remember: Before Sanders ran in 2016, she was the one who was the progressive movement draw. Now, Sanders and to a somewhat lesser extent, Beto O'Rourke and Buttiegieg, are seen as the movement candidates.

6. Does Beto O'Rourke get edged out or does he find his way in? Behind the scenes, Sanders' campaign and groups helping him have taken aim at O'Rourke. After all, the former Texas congressman is on par with, but a little behind, Sanders when it comes to grassroots fundraising. And people close to Sanders have made the case that O'Rourke is not all that progressive (his biggest sin: giving fast-track authority to President Obama for the Trans-Pacific Partnership, or TPP).

He still has a certain "it" factor, but Buttigieg's gain has been O'Rourke's loss, as they're taking up a similar space in the Democratic nomination fight. There have been questions about O'Rourke's experience and the depth of his plans and ideas. He needs to show himself to be presidential material and a heavyweight in the debates who is not overshadowed.

7. Can Kamala Harris supercharge her candidacy – and fend off Biden in South Carolina? The idea of Harris is one Democratic voters like – a black woman and former prosecutor as an answer to Donald Trump. But the reality has been less than overwhelming so far. The California senator has shown herself to be cautious as a candidate, which may have allowed room for other candidates to gain attention in spaces that she could have owned.

She is a clear thinker and gained attention for her questioning of Brett Kavanaugh during his 2018 confirmation hearings. She's going to need her calm and precision to stand out in the debates. One thing she does have is money. Harris raised $12 million in the first quarter, and if she can keep her base of California donors on board, she could be in it for the long haul. But Harris needs to shore up her support in early primary states. Key to that is South Carolina, the first primary with a predominantly black electorate, but Biden complicates that calculation.

8. Can others have a breakout moment? There are a dozen other declared candidates in the race, not mentioned above. They include Sens. Amy Klobuchar of Minnesota and Cory Booker of New Jersey; Govs. Jay Inslee of Washington and John Hickenlooper of Colorado; members of the House like Eric Swalwell, Seth Moulton and Tim Ryan. And there are outsiders like tech startup investor Andrew Yang and New Age author Marianne Williamson.

Some are focusing on issues hoping to distinguish themselves, like Inslee on climate change or Swalwell on gun safety. They all may qualify for the first sanctioned Democratic primary debate in June in Miami, and they are going to need a breakout moment in those to spur earned media attention and light a fuse with the grassroots to continue on for the long haul.

Copyright 2019 NPR. To see more, visit https://www.npr.org.