Let the battle for New York enter its final phase. Democratic frontrunner Hillary Clinton and her recently surging competitor Bernie Sanders will debate for the ninth time in Brooklyn, where Sanders was raised, on Thursday night. The Empire State's primaries — Democratic and Republican — are on Tuesday, and there are 291 total Democratic delegates up for grabs.

Sanders has won seven Democratic nominating contests in a row, and according to the Associated Press, he has 1,069 total delegates to Clinton's 1,758. Although unlikely, a big win in New York would cut into Clinton's delegate lead. A tie or a small victory may be moral victories for Sanders, but it does not help his mathematical chances, and it is not as persuasive for the unpledged, or super, delegates as a large victory would be.

According to RealClearPolitics, Clinton has consistently been polling ahead of Sanders by double digits, and the RCP Average has her up by 13.3.

The candidates could go in multiple directions, but either way, it is likely going to get ugly — at least for Democratic standards.

Sanders will likely bring up all of his major issues, including: income inequality, Wall Street, the economy, trade and fracking. Where is a better place to bring his message about income inequality than New York City, which is one of the places in this country where the problem is most evident.

The economy and trade are traditional segments in Sanders' speeches when he takes the stump and debate stage. The economy goes into Wall Street because of the greed and big business he associates with it, but he will also incorporate jobs and, likely, the need to improve the economic conditions upstate.

Fracking will no doubt take up a significant portion of one of the segments because of New York's strong anti-fracking sentiment. There is also a stark contrast between him and Clinton for he is against it in all circumstances, while the former chief diplomat is against it if a series of conditions cannot be met, but she says her conditions would be too tough for any company to try to comply with.

The Vermont senator will go after Clinton for her Wall Street speaking fees, which has been the subject of jabs in previous debates. He has been able to back up this attack on his by saying that "the people" own his campaign, and he has a record number of individual donors. There is no doubt this theme will continue on Thursday's stage.

Sanders will need to keep his cool, however, so he does not have another moment where he questions her qualifications, as he recently did. Since clarifying that contentious statement, Sanders has gone back to his message of questioning her judgment instead of her qualifications. He'll need to avoid a similar misstep or risk turning off voters.

Pressure is also high on Clinton to perform well, after her campaign had its own rough, racially insensitive patch, which was capped off by what some viewed as a racist skit with New York City Mayor Bill de Blasio. She cannot do anything else to jeopardize the African American vote.

There is no doubt, however, that she will continue to play the home state card — which Sanders will likely also try — and attack Sanders for his policies that she and at least some of her supporters see as not practical. She will say that she has real, attainable solutions and that she knows what is best for the people of New York and the country.

She may even go after him for taking a trip to speak at a Vatican conference, but he could go after her for needing to do a fundraiser with actor George Clooney and his wife.

Clinton, like Sanders, cannot afford to turn people off because right now the polls suggest that this is her primary to lose, and Sanders can take any opening and turn into a big gain. Thus, she should also keep her cool and so she does not upset those who are on the fence. She should also not do anything that could push away Sanders' supporters any further because she will need them if she is the Democratic nominee.

If Sanders wins the debate, he improves his Tuesday prospects. If he does not win, it is extremely unlikely that his prospects improve.

Thursday's showdown starts at 6 p.m. PDT on CNN (and NY1); it will take place in the Duggal Greenhouse.

Reach News Editor Max Schwartz here; follow him on Twitter here.