WASHINGTON — At last night’s Democratic debate, Joe Biden sometimes thrived and sometimes just survived — a definite improvement from last month; Kamala Harris struggled compared with her first outing; and Cory Booker and Michael Bennet stood out.

But our main takeaway from last night was how combative it was for this early of a Democratic debate — in so many different directions.

You had:

Biden challenging Harris on her new health care plan.

Julian Castro hitting Biden on immigration.

Harris and Booker taking on Biden’s record on crime and busing in the 1970s.

Biden pushing back at Booker on his policing record as Newark mayor.

Tulsi Gabbard going after Harris on her record as California attorney general.

Kirsten Gillibrand taking a shot at Biden on women in the workforce (and missing badly).

Harris fighting Biden on abortion and the Hyde amendment.

And Jay Inslee knocking Biden over his vote for the Iraq war.

So if the first round of Dem debates underscored how far to the left the party has moved since Barack Obama left office, the second round highlighted how willing they are to attack one another, even when they agree on the vast majority of issues.

Of course, politics ain’t beanbag. And presidential debates are SUPPOSED to produce conflict and disagreement.

But play out seven or eight more months of these same kinds of debates, and you can see why an incumbent president — especially one who gets to avoid a real primary challenge — has a SIGNIFICANT advantage.

That includes an incumbent as vulnerable as Trump.

Like George W. Bush in ‘04 or Barack Obama in ’12, they get to avoid these televised food fights.

More than anything else, last night’s Dem debate marked the end of the nice, kid-gloves phases of the race.

Phase One was the candidate introductions. Phase Two was the polite, gentle sorting into different tiers and lanes.

Now we’re entering Phase Three — the hand-to-hand political combat.

All with 186 days until the Iowa caucuses and 194 days until New Hampshire.

Breaking down the performances

Watching Biden was — for us Washington Nationals fans — like watching the Nats bullpen: good enough to be moving up in the standings, but still making you nervous.

When Harris is at her best, she’s a happy warrior. And she wasn’t a happy warrior last night. Also, on the biggest policy issue for Democrats (health care), she just isn’t that comfortable.

Booker did everything he needed to do — he got to play nice and aggressive when he wanted to, without many attacks coming his way. If last night can’t move the needle for him, what will?

And finally, if the social metrics are meaningful, then Andrew Yang and Tulsi Gabbard had breakout performances — like Marianne Williamson the night before.

But our question: Does performing well on social metrics translate to the polls? We’ll find out.

2020 Vision: Heading to Cincinnati

The day after last night’s Dem debate, President Trump heads to Cincinnati, where he’ll hold a campaign rally at 7:00 pm ET.

On the campaign trail today

After last night’s debate, Joe Biden holds an event in Detroit… Kamala Harris gaggles with reporters in Motor City… And Cory Booker also makes an appearance in the city… Elizabeth Warren has a town hall in Arizona… And Beto O’Rourke stumps in Nevada.

Dispatches from NBC’s embeds

At a South Carolina debate watch party, where most attendees were Biden supporters, NBC’s Jordan Jackson reports what one woman thought of the Democratic field: “I think this country is so divided with racism, and what Donald Trump is doing, and the mindset of this country, I think it's going to take a white man to beat Donald Trump. And I think his mannerism, it's going to take another one to put up against him. And I think that would be Joe Biden.”

In Iowa, it’s a tale of multiple winners. NBC’s Priscilla Thompson reports from a Polk County Democratic watch party where Biden won the night, per the attendees.

“Everyone I spoke to thought Biden did great. “The narrative coming in, was knives are out for Joe Biden someone’s going to tackle him, How's he going to react?” Dave Musgrove said. “I think that everyone went for Joe Biden tonight. None of its really seemed to lag because the standard is what Kamala Harris did in the previous debate and I don't think anyone's ever going to clear that again, ironically, not even Kamala Harris.”

In Waukee, Iowa NBC’s Maura Barrett reports that voters don’t think any one candidate won the evening, but they liked Cory Booker and Kamala Harris’ performances.

Tweet of the day: So here’s my number, so text me maybe

I remember Bob Dole trying to give out his campaign web address in his closing statement in a 1996 debate and it sounded a bit like Biden giving out his text number at the end — Steve Kornacki (@SteveKornacki) August 1, 2019

Data Download: And the number of the day is … 21 minutes, 21 seconds.

That's how much time Joe Biden spoke during last night's debate, according to a count by NPR.

Kamala Harris had the second-most speaking time, at 17 minutes and 43 seconds.

And Cory Booker came in third, at 12 minutes, 52 seconds.

Biden spoke for the longest of any candidate on the two nights. Both Elizabeth Warren and Bernie Sanders led Tuesday night's speaking times, with about 17 minutes apiece.

The Lid: The Social Network

Don't miss the pod from yesterday, when we looked at what polling shows about perceptions of socialism.

ICYMI: New clips you shouldn’t miss

Here's our team's fact check and live blog from last night's debate.

Alex-Seitz Wald sums up the sparring between Biden, Harris and Booker.

And Benjy Sarlin notes that, in between the jabs, there were some meaty policy debates as well.

Trump's rally tonight in Ohio will be the first since the "send her back" chant.

And the latest revelations about Jeffrey Epstein are... ew.

TRUMP AGENDA: No medals for you

The president is ordering the Navy to strip medals from prosecutors in the trial of a Navy SEAL accused of war crimes.

The new crop of Republican retirements could complicate the party's hopes of taking back the House.

Here's what you need to know about the Fed's rate cut.

2020: A B-minus for Biden

The New York Times' lead analysis piece: "Joe Biden did fine, and that might have been enough."

Dan Balz of the Washington Post calls the personal squabbling over character "a foreboding turn for Democrats."

George Soros is launching a 2020 superPAC.

Eric Garner's death became a major topic at last night's debate.

Check out embed Maura Barrett's latest piece on Democrats campaigning in Steve King country.