(This is the 13th edition of our power rankings of Democrats most likely to get their party's presidential nomination in 2020.)

(CNN) The first debates are coming.

In just over a month -- on June 26 and 27 in Miami, to be exact -- the 2020 Democratic presidential race will begin in earnest with as many as 20 candidates debating over two nights.

Until then, the race to be the Democratic nominee against President Donald Trump remains in a bit of a holding pattern. Candidates who have yet to qualify for the debate are doing everything they can -- raising money, mostly -- to ensure they don't get left off the stage on one of the two nights. Those who are comfortably in are working to keep from making any mistake(s) that would hurt their momentum going into Miami next month.

Below, our rankings of the 10 men and women most likely -- as of today -- to wind up as their party's nominee. We've got two new faces this time around -- see below for who they are -- which means two people had to drop off the list. Those two? Former San Antonio Mayor Julián Castro and New York Sen. Kirsten Gillibrand.

10. Andrew Yang: Once you get past the first seven-ish candidates, it gets very hard to differentiate between the next 10. But here's the case for Yang: He's built a large and aggressive online community. And he crested the 65,000 individual donor plateau -- one benchmark for qualifying for the first debates next month -- way back in mid-March. He's also averaging 1% in the Real Clear Politics average of national polling, which is better than, say, Gillibrand. (Previous ranking: Not ranked)

9. Steve Bullock: The governor of Montana takes over the ninth spot after announcing his campaign last week. He had a good first week, announcing that he raised $1 million in the first 24 hours and earning the endorsement of the most popular Democrat in Iowa (Attorney General Tom Miller). And he's basing his campaign pitch on being a Democrat who can win in a red state -- exactly the type of message that could resonate in a year in which Democrats prize electability. Bullock's problem is that he needs to become better-known (and probably needs Joe Biden to stumble) to carry the electability mantle. (Previous ranking: Not ranked)

8. Cory Booker: Booker continues to be a man in search of a moment in the 2020 race. This week might have been that chance -- a planned MSNBC town hall in Iowa -- but the New Jersey senator had to cancel due to votes back in DC. Booker is fighting like hell to be the liberal flag-bearer in the race (he announced a series of executive actions he would take to protect abortion rights if elected) but so far hasn't been able to find much success. (Previous ranking: 8)

7. Beto O'Rourke: The former Texas representative had his best night in a while thanks to his performance in his Tuesday CNN town hall. He's going to need more of those to erase a perception that he's all hat and no cattle. O'Rourke's campaign has been in reboot mode over the last few weeks, as his poll numbers have tumbled. He sank to 2% in a recent national poll from Quinnipiac University, and is faring no better in the early states. His low point might have been when he admitted on "The View" that his appearance on the cover of Vanity Fair was a mistake. (Previous ranking: 6)

6. Amy Klobuchar: The Minnesota senator marked her 100th day in the race earlier this week and continues to slowly but surely climb up our rankings -- thanks in part to the faltering of her rivals once ranked above her. Klobuchar's campaign is built around the idea of steadiness and grit, and to date, she has displayed both as she hangs just off the main pack. (Previous ranking: 7)

5. Elizabeth Warren: The (mostly good) press seems to be coming in droves for the senior senator from Massachusetts. Appearing on the cover of Time magazine, a story about how she is connecting with black women and coming in third for cable news mentions are likely all helping Warren. And she's now placing third more often than not in national polls, just ahead of Buttigieg and Harris. The question for Warren going forward is whether she can actually start appealing to voters who don't have a college degree or call themselves very liberal. If she can't, her ceiling is limited. (Previous ranking: 5)

4. Pete Buttigieg: Buttigieg's surge is over -- for now. He went from 10% in an April Quinnipiac University survey to 5% in a May poll. That sort of settling is normal; no candidate surges for a year straight before a single vote is cast. And the South Bend mayor has to be happy with where he stands at the moment -- money, a rapidly growing staff in early states and nationally, and poll numbers that suggest he's got room to grow. (Almost 6 in 10 in the Q poll didn't know enough about Buttigieg to offer an opinion.) (Previous ranking: 4)

3. Kamala Harris: Just like O'Rourke, the junior senator from California seems intent on rebooting her campaign. Harris has stalled in recent months as her left-leaning campaign has run into a classic clown-car problem: Almost everyone in the race is running left. She now seems to be trying to split the difference between those on the left (Sanders and Warren) and those closer to the center (Biden). Can this "Goldilocks" campaign work? Or is Harris going to just be this year's version of Marco Rubio (i.e. trying to satisfy all and satisfying few)? (Previous ranking: 3)

2. Bernie Sanders: Sanders is starting to draw a distinction between the races that he and Biden are running; Sanders paints his as a cause for broadscale change of society, while he casts Biden's as just another campaign in a long line of them. Sanders is also going to start holding in-person fundraising events, a change from his 2016 all-online approach and a recognition that he may not be able to keep pace with Biden (and others) if he only relies on online donations. (Previous ranking: 2)

1. Joe Biden: The former vice president remains the front-runner thanks to consistently polling 20 points or more ahead of the field. Biden's also doing this his way. He's stayed on message by focusing his attention on Donald Trump rather than his Democratic opponents. Additionally, Biden hasn't shied away from big donors, and has pulled in millions of dollars as a result. This includes taking in over $2 million from a Florida fundraising blitz this past week. If you're looking for bad news, you can make out a slight decline in Biden's poll numbers from the high 30s after launch to the mid-30s in the past few days. But that's a within-the-margin-of-error shift. (Previous ranking: 1)