Democrats hoping that Wednesday night’s first presidential debate of the 2020 campaign would help clarify some issues were probably disappointed. There were no major stumbles, but few standout moments as 10 candidates vied for the nation’s attention.

Here are some of the key points:

Warren and Castro lead the way

Massachusetts Senator Elizabeth Warren dominated the debate’s opening moments, calling for systemic change to the nation’s economy and the end to the private insurance system.

Ms Warren was the highest-polling candidate on stage and NBC moderators repeatedly tried to draw her rivals into challenging her liberal policies. But they largely passed on those opportunities, even when Ms Warren was virtually alone in her stance on overhauling the healthcare industry.

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Senator Elizabeth Warren dominated the opening of the debate (Wilfredo Lee/AP)

Former housing and urban development secretary Julian Castro, who has struggled for months to break through in the crowded field, asserted himself as a leader on immigration, an issue sure to be at the forefront of the general election campaign against President Donald Trump.

He challenged his rivals to join him in rewriting immigration laws so that mere illegal entry into the United States would no longer be a federal crime.

The question is whether Ms Warren and Mr Castro’s performances still stand out after night two of the Democratic debate on Thursday, when former vice president Joe Biden and nine other candidates take the stage.

Whose economy is it anyway?

The debate kicked off with moderator Savannah Guthrie asking Ms Warren if her many ambitious plans — free college, universal childcare and healthcare — would hurt a booming economy.

“Who is this economy really working for?” Ms Warren replied. “It’s doing great for a thinner and thinner slice at the top.”

Her response was echoed by other Democrats.

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Former Texas Representative Beto O’Rourke condemned President Donald Trump’s tax policy (Wilfredo Lee/AP)

“Donald Trump just sits in the White House and gloats about what’s going on, when you have so many people that are having trouble affording college and having trouble affording their premiums,” said Minnesota Senator Amy Klobuchar, a moderate who declined to take a swipe at Ms Warren’s ambitious plans.

Former Representative Beto O’Rourke of Texas condemned Mr Trump’s tax cut as part of “an economy that is rigged to corporations and to the very wealthiest”.

And Representative Tim Ryan, who represents several declining industrial areas in Ohio, said: “This issue we’re talking about has been going on for 40 years.”

Only former Representative John Delaney of Maryland clearly disagreed and said many of Ms Warren’s promises were not realistic.

How far on immigration?

No issue in the first Democratic debate showcased the contrast with Mr Trump more than immigration. But the issue also exposed significant rifts among his challengers — namely the two Texans on the stage.

Mr Castro took aim at Mr O’Rourke, who has campaigned heavily on border issues, for not proposing to decriminalise illegal migration in his immigration blueprint. Such a step would make a significant change to US immigration law.

“If you truly want to change the system, we have to change that section” of federal law, said Mr Castro.

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Former housing and urban development secretary Julian Castro spoke in Spanish during his closing statement and talked about saying “adios” to Donald Trump (Wilfredo Lee/AP)

Mr O’Rourke said he wanted to keep the provision so authorities could pursue drug and human traffickers. But Mr Castro cut him off, noting that there are separate laws that could be used against those crimes, and the entire stage broke down into crosstalk and shouting.

Several other contenders — including Ms Warren, New Jersey Senator Cory Booker and Washington Governor Jay Inslee — have already signed up to Mr Castro’s approach.

Appeals to diverse base

The diversity of the modern Democratic Party was on display on Wednesday night — three women, one black man and a man of Mexican heritage vying for the presidential nomination. And the candidates made sure they were speaking to the party’s base, which is becoming younger and less white.

Mr O’Rourke showed off his fluent Spanish in his opening statement.

Mr Booker countered with his Spanish during a discussion of immigration, and also noted that he is probably the only candidate who lives in a poor, predominantly minority community (Newark).

Election 2020 Debate
Senator Cory Booker noted that he is probably the only candidate who lives in a poor, predominantly minority community (Wilfredo Lee/AP)

Mr Castro spoke in Spanish during his closing statement and talked about saying “adios” to Mr Trump.

New York Mayor Bill de Blasio noted that he has an African-American son as he urged the party to “stop acting like the party of elites”.

A new Democratic bogeyman?

Perhaps the hardest question for Democrats to answer was how the candidates would deal with a Republican. Not Mr Trump, but Senate Majority Leader Mitch McConnell.

Republicans have a good chance of still controlling the Senate even if Democrats win the White House in 2020, and it is unlikely Mr McConnell would allow any of the candidates’ ambitious proposals on government-run healthcare or green energy to become law.

Ms Warren promised she had a plan to deal with Mr McConnell, though it seemed to centre on rallying public opinion against him.

“We have to push from the outside and lead from the inside,” she said.

Mr Booker proposed that the party’s presidential nominee campaigns in longshot states like South Carolina in the hope of snaring enough seats to take over the Senate.

Mr Inslee suggested eliminating the filibuster — which the president cannot do and which would strengthen Mr McConnell’s hand if the GOP remained in the majority.