Joe Biden and Donald Trump are gearing up for a rematch in the first 2024 US election debate. 

It's the third faceoff between the President and former President after two heated encounters in 2020. 

Marco Rubio's former chief of staff Matt Terrill says Biden will have to bring some energy while Trump will have to focus on the policies.  

He told Mike Hosking that it's going to come down to inflation and immigration.  

Terrill says those two issues are top of mind for the undecided voters, who both candidates will be trying to win over. 

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