The decision to replace Joe Biden as the Democratic nominee would not be simple, and it is still unlikely. While there are scenarios in which the party could choose an alternative to Biden, such as if he steps down voluntarily or is physically unable to continue, at this point Biden remains the candidate.
His main opponent, Dean Phillips, has struggled to gain support for his warnings about the risks of Biden’s candidacy and has been largely ostracized from the party. Furthermore, a new candidate entering the race this late is not a viable option.
Given these limitations, the only viable backup plan involves Biden voluntarily stepping aside. One way this could play out would be for Biden to win the primary election and then announce that he is not accepting the nomination, allowing his delegates to support another candidate. This would trigger a new phase of the election with other potential candidates vying for the nomination.
If Biden were to retire, there would be a scramble among potential successors within the Democratic Party to take his place. This could be an intense political battle with various candidates seeking to position themselves for the nomination.
For the Republican Party, Trump’s candidacy also raises concerns due to his age and legal issues. However, the Republican convention rules are different from the Democratic party’s in that they are tied to their candidate and cannot easily remove him from the nomination.
Both parties face similar challenges in the event of a candidate being unable to compete, and it’s clear that in an era of weakened national parties, there are few viable replacements of stature who can keep the party or perhaps the nation in good shape. As a result, both Biden and Trump are likely to remain as the candidates for their respective parties.