Hillary Clinton and Beie Sanders shelved the niceties and went right after each other’s perceived weak spots at a must-win Democratic primary debate Thursday night where the front-ruer targeted her rival’s grasp of complex policy issues – and the insurgent senator hammered her as a Wall Street pal just now talking the talk of working Americans.

The charge crystallized when Clinton seemed to surprise Sanders by declaring she’d backed legislation for a $15 federal minimum wage.

“To suddenly aounce now you’re for 15, I don’t think is quite accurate,” Sanders said, noting Clinton previously has pushed for increasing the hourly wage to $12. “I think the secretary has confused a lot of people.”

However, Clinton said she both supports the goal of raising the wage to $12, while encouraging some jurisdictions to go higher. But she said if there’s a Democratic Congress to pass a $15 wage, she would back that legislation.

“I have said from the very begiing that I supported the fight for 15,” Clinton insisted.

The heated dispute, in which the candidates frequently interrupted each other, was one of many at a debate heavy on populist rhetoric. The two were facing off during the CNN-hosted forum in Brooklyn for their first debate in more than a month at a critical time. The campaign heads soon into the final stretch with the upcoming New York primary seen as a determining factor.

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While both candidates courted Empire State voters Thursday by stressing their New York ties, more broadly they spent the night appealing to working-class voters.

At the same time, the debate veered heavily into foreign policy in the second half, with Sanders using the issue to challenge Clinton’s judgment while she questioned his experience.

“Describing the problem is a lot easier than trying to solve it,” Clinton said at one point, challenging Sanders as he laid out his goals for achieving Middle East peace.

Sanders, as he has before, hammered Clinton for supporting regime change in Libya and Iraq, waing that it has “unintended consequences.” He said the former secretary of state’s continued support for a no-fly zone in Syria – which he noted President Obama does not support – “runs the risk of getting us sucked into perpetual warfare in that region”

But Clinton defended her stance, and argued: “Nobody stood up to Assad and removed him and we have had a far greater disaster in Syria.”

Earlier, Sanders also pointed to Clinton’s support for the Iraq war, as well as “virtually every disastrous trade agreement,” in challenging her “judgment” to lead.

However, Clinton fired back, pointing to a challenging editorial board meeting Sanders had with the New York Daily News where he seemed to struggle to explain his plan to break up the banks and various foreign policy positions.

“He could not explain how” he would break up the banks, Clinton said. She defended her own judgment and said: “I think you need to have the judgment on day one to be both president and commander-in-chief.”

While the tone was tougher than past face-offs, the candidates hit several familiar themes. Clinton suggested Sanders is too closely aligned with the gun industry. Sanders knocked Clinton for not releasing transcripts of her past paid speeches.

On that point, Sanders said that despite the financial industry-fueled recession, “Secretary Clinton was busy giving speeches to Goldman Sachs for $225,000 a speech.”

Clinton, though, denied that any of that money influenced her decisions in office. Further, she said, “I stood up against behaviors of the banks when I was a senator.”

Sanders gave a sarcastic retort: “Oh my goodness. They must have been really crushed by this.”

Sanders has been on an election roll lately, wiing seven of the last eight state contests, most recently in Wyoming over the weekend. On stage Thursday, he touted his “landslide victories” in recent contests.

But analysts note the primary map could soon be tuing back in the front-ruer’s favor, not only in New York but other Easte primary states.

With the stakes getting ever-higher, the tone of the contest has sharpened. Sanders recently alleged Clinton may not be qualified for president, before walking back the remark. And the Clinton campaign has criticized Sanders for the aggressive efforts by some of his supporters to persuade so-called superdelegates to back the Vermont senator.

Superdelegates are elected officials and other party insiders free to support whomever they want. Most of them are siding with Clinton, giving her an even wider delegate lead.

Going into the Empire State primary on Tuesday, Clinton so far has held the lead in most polls. Clinton spent eight years as a New York senator.

But Sanders, a Vermont senator who was bo in Brooklyn, has been touting his local roots as he seeks to upset Clinton in the state.

While Sanders is on a wiing streak in primaries and caucuses, he desperately needs a big victory in New York if he hopes to cut into Clinton's delegate lead and slow her march to the nomination. To date, Clinton has accumulated 1,758 total delegates, compared with Sanders’ 1,069. It takes 2,383 to win.

The Associated Press contributed to this report.