What will the difference be between the national popular vote, and Nate Silver's polling average, for the 2024 US Presidential Election - in other words, what is the polling miss for the year?

The miss will be expressed as the poll bias: for example, if the national popular vote is D+2, and the polling average is D+5, this will resolve to a D+3 miss.

Given the long tail of mail in and corrected ballots, I intend on resolving this one month after the election - though if there is a major legal fight over ballots I might resolve it at the time of inauguration, or if the answer is not close to changing brackets (e.g. <0.1% of votes expected to change) I may create a poll to resolve the market early.

The polling average used will be the final pre-election average found here: https://www.natesilver.net/p/nate-silver-2024-president-election-polls-model

The national popular vote will be aggregated from various state Secretary of State releases, and is usually identical between all major data providers. (A single source could be provided later if this is a sticking point for anyone, but I haven't seen substantial disagreements.)