Paul Singer, and Cooper Allen

USA TODAY

Hillary Clinton and Bernie Sanders bellied up to the podiums for the ninth Democratic presidential debate Thursday, a milestone that seemed inconceivable when she launched her campaign a year ago as the overwhelming front-runner.

Here are a few takeaways from the DonnyBrooklyn:

Bernie makes a bit of news

Sanders, pushed by Clinton to publicly release his tax returns, announced 1) that his wife Jane handles the taxes for the family and she has been really busy, and 2) he will release his most recent tax return Friday, and other years shortly thereafter. "They are very boring tax returns," Sanders promised. "No big money from speeches, no major investments. Unfortunately, I remain one of the poorer members of the United States Senate." Clinton made no comparable news when pressed to release the transcripts of her privately paid speeches to Wall Street firms, repeating her defense that she will only release them when all the presidential candidates agree to release their private speeches.

How many people on stage?

Clinton made every effort to make sure that Sanders was debating not just her but her husband, former president Bill Clinton, and President Obama, her former boss. When Sanders attacked her for having a super PAC supporting her, she said "this is not just an attack on me, it's an attack on President Obama," because Obama also had a super PAC and yet did not kowtow to big donors. When Sanders said Clinton was soft on climate change, she pointed to her role in Obama's successes. "I'm getting a little bit concerned here because, you know, I really believe that the president has done an incredible job against great odds and deserves to be supported," she said. The former first lady said the crime bill her husband signed achieved some good things, despite concerns that it drove harsh sentences around the country, particularly for non-violent drug offenders. And when asked whether she would apologize for the excessive harshness of the law, she said, "My husband has apologized. He was the president who actually signed it."

Mideast politics

Sanders has for a while now taken on Clinton over her 2002 Senate vote authorizing the Iraq War, which came up again Thursday night. But perhaps the most extended foreign policy exchange of the night was over their approaches to the long-simmering dispute between Israel and Palestine, long a key issue in New York. Sanders, who is Jewish, asserted that Israel unquestionably had a right to defend itself, but he argued for a much more balanced approach to dealing with the region, while reiterating his belief that Israel's operation in 2014 in Gaza was a "disproportionate attack." Clinton cited her past efforts in the region but was much more critical of Palestinians. Perhaps most noteworthy was Sanders' forceful critique of Clinton for not reaching out more to the Palestinians. "You gave a major speech to AIPAC, which obviously deals with the Middle East crisis, and you barely mentioned the Palestinians," he said.

"All that I am saying is we cannot continue to be one-sided," he said in concluding the exchange. "There are two sides to the issue."

Justice Merrick Garland? Not if there's a President Sanders

The Senate Republican leadership has made clear since the day Justice Antonin Scalia died that an Obama nominee would not get a vote in 2016. Clinton and Sanders, not surprisingly, were united in their opposition to this approach. Clinton on Thursday night said "the president is on the right side of both the Constitution and history" and challenged the Senate to act. Sanders called the situation "an outrage." However, when it came to the merits of Garland himself, things got a bit more complicated. When asked what she would do if she wins and the nomination is still pending, Clinton said, "I will take stock of where we are and move from there." Sanders was much more definitive. He said that, while he'd back the Garland nomination as a senator, if he is nominated and wins in November, "I would ask the president to withdraw that nomination" because Garland has not made "crystal clear" whether he would support overturning the Citizens United decision that led to the creation of super PACs.

Straight outta Brooklyn

The New York primary is considered a critical contest for the Democratic nomination, but both candidates are heading for the airports. Sanders is flying to the Vatican for an academic conference on social and economic inequality; Clinton is heading to California for a round of campaign events and fundraisers. He apparently won't see the pope, but she apparently will see George Clooney. (Advantage: Clinton)