(CNN) As Joe Biden is set to debate one-on-one against Bernie Sanders for the first time, the former vice president Sunday night will attempt to make overtures to the Vermont senator and his supporters on areas where they can find common ground, an aide to Biden said.

Biden will do this while also presenting his case for why he should be the Democratic nominee and why he is best positioned to beat President Donald Trump , the aide said.

The expected effort showcases one of the tasks Biden faces as he works to secure the Democratic presidential nomination -- making the case for his brand of politics while not alienating Sanders' fervent supporters, which the former vice president would need to win over heading into a general election.

Biden previewed one possible overture Friday when he announced his endorsement of Massachusetts Sen. Elizabeth Warren's bankruptcy proposal , which includes student loan debt relief in bankruptcy. Biden called the proposal "one of the things that I think Bernie and I will agree on." As CNN previously reported, a Biden campaign aide said the former vice president would likely say more about his support of the proposal in the debate Sunday night.

On Wednesday, Sanders previewed some of the issues he plans to press Biden on, including health care, climate change and economic inequality.

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