MILWAUKEE — The debate was in Wisconsin. The audience — the one that mattered — was in Nevada’s Clark County and South Carolina’s midlands. It didn’t need to work very hard to hear the sale.

“We have a lot more social media; we have everybody with a cellphone,” said Hillary Clinton, to voters who had seen videos of black men killed during confrontations with police. “So, we are seeing the dark side of the remaining systemic racism that we have to root out in our society.”

“We’ve got 11 million undocumented people in this country,” said Bernie Sanders, to Latino voters who were nervously watching the rise of Donald Trump. “I have talked to some of the young kids with tears rolling down their cheeks, are scared to death that today they may or their parents may be deported.”

This was the last debate before millions of votes would be cast in Nevada, South Carolina and a March 1 slate of states that encompasses most of the South. The only real debate in Democratic politics (and among nervous investors) at the moment is whether those states are, as the statistical models suggest, better for Clinton than Sanders. Clinton, after losing New Hampshire in a landslide and leaving Iowa with a “tie” that has caused serious bitterness among Sanders fans, was the weakened candidate but the one with the most promising elections ahead of her.

Understanding that, Sanders has waged a happy war of attrition on Clinton’s base of black and Latino voters. He’s had surprising success, convincing Black Lives Matter activists, black intellectuals, and state legislators that he has the most serious and comprehensive approach to criminal justice reform and economic fairness.

On Thursday, he revealed no new weaponry. Asked if race relations would improve in a Sanders presidency, the Vermont senator said “absolutely, because what we will do is say, ‘Instead of giving tax breaks to billionaires, we are going to create millions of jobs for low-income kids so they’re not hanging out on street corners.’ ”

It was the answer he’d given since July 2015; it was the answer, really, that he’d given throughout his career, democratically socialist but unspecific. It also avoided the brickbats that had been brutal for Clinton when wielded by Sanders surrogates like Cornel West: donations for the Democratic frontrunner from the private prison industry, the cruelty of welfare reform. Sanders, who has managed to push negative arguments about Clinton through “contrast” ads, declined to inform the TV audience of this.

He was tougher on immigration, though not as tough as he might have been. He demanded some accountability from Clinton on her politic response to the 2014 child migrant crisis. She had called for children fleeing violence in Central America to be “reunited with their families.” He had “thought it was a good idea to allow those children to stay in this country.” But the short-term impact of that crisis, on domestic policy, was that Republican politicians cited it as a reason to squash immigration reform. Sanders, whom Clinton had criticized for opposing a 2007 reform bill, tried to explain that he did so because some (far from all) advocates called it flawed and called guest worker programs slavery-like.

“I used to work for Senator [Ted] Kennedy,” said Secretary of Labor Tom Perez, who came to Milwaukee to spin for Clinton. “It’s insulting to suggest that Senator Kennedy would support anything that’s akin to slavery. So let’s clarify that. The challenge in the 2007 vote is that, while Senator Sanders was well-intentioned, when you insist on the perfect you get nothing done... the DREAMers that I meet are not waiting for revolution.”

The calculation of Clinton supporters is that Sanders’s idealism can win over white liberals — more than they thought it could, honestly — but hit a wall with the party’s black and brown base. When Clinton was in a tough spot, she hugged the president. She had a super PAC? Well, so did Barack Obama. She took money from Wall Street? Well, so did the first black commander-in-chief. Clinton even got away with calling Priorities USA a mere PAC “that was set up to support President Obama, that has now decided that they want to support me,” not the attack dog it had become.

Sanders, again, either missed or did not take opportunities to call this out. Clinton lumped Countrywide in with the corporations that she would be tough on. Neither Sanders nor the moderators chose to mention that in 2008 Clinton counted on campaign help and money from Henry Cisneros, a veteran of her husband’s administration who had become a board member of Countrywide.

The senator chomped much harder on a statement Clinton had made in last week’s debate. “I was very flattered when Henry Kissinger said I ran the State Department better than anybody had run it in a long time,” she had said. It caused a flurry on Twitter (what doesn’t?), and Sanders came ready to rebut that.

“Kissinger’s actions in Cambodia, when the United States bombed that country, overthrew Prince Sihanouk, created the instability for Pol Pot and the Khmer Rouge to come in, who then butchered some 3 million innocent people, one of the worst genocides in the history of the world,” he said. “So count me in as somebody who will not be listening to Henry Kissinger.”

Clinton’s campaign could not figure out why Sanders did this. Which of the coming primary voters would be moved? Why did the candidate pulling in up to 85 percent of millennials need to prove, again, that he could mind-meld with undergrads? He was right and she was wrong but it was on a topic she didn’t really care if she was wrong about. Plus, she did better when buffaloing Sanders over the votes to topple Libya’s government in 2011.

“Everybody voted for it wanting to see Libya move toward democracy, of course we all wanted to do that,” he said. “That is very different than talking about specific action for regime change, which I did not support.”

“You did support a U.N. Security Council approach, which we did follow up on,” countered Clinton. If all she could do was neutralize Sanders’s advantage on these issues, she would take it.