Here are five things to watch for when Kamala Harris and Donald Trump meet at 9pm in Philadelphia.
Who will look more presidential?
The spotlight will shine particularly brightly on Harris, because Trump is better known to voters. The former president will still be scrutinised, as he has struggled to adjust to his new rival, relying on personal attacks against the vice-president.
Who will define Harris?
Both candidates will be trying to do a simple thing during the debate: to define Harris for a voting public that knows much less about her than about Trump.
Will Harris the prosecutor go after Trump the felon?
Harris has made her experience as a prosecutor a central part of her political identity, and has been more willing than Biden to go after Trump on the campaign trail for his criminal convictions.
Whose economic vision will resonate?
Harris and Trump will lay out their competing economic visions for how to bring down the country’s high cost of living. Trump wants to lower taxes, beyond extending the cuts he passed in 2017, boost energy production, slash government spending and enlist Elon Musk to pursue aggressive deregulation. Harris wants to raise taxes on wealthy earners and large corporations to widen the social safety net and give child care tax credits and tax benefits to small business owners.
Who will be stronger on the flashpoints of immigration and abortion?
Trump has been on the defensive on abortion rights and is struggling to define his position. Harris, who has campaigned strongly for reproductive rights, will try to link the former president to the 2022 overturning of Roe vs Wade by the Supreme Court. The ex-president will seek to hammer the Biden administration for an influx of migrants across the US-Mexico border under its watch.
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