The majority doesn’t matter because of gerrymandering and the electoral college. AFAIK the majority of Republicans are not opposed to it. A simple majority that might exist does not matter if the other absolute majority of the other options is bigger. You are also acting as if it wouldn’t be politicized and propagandized if suddenly one group started coming out against Israel, which would significantly affect polling from independents and break away republicans. Politics are a reactive environment, not a static one.

Support for Israel has been very high historically in the US. It is only recently where it has declined significantly, and not really enough to make it not be the elephant in the room. And I can assure you, any relation you see between this issue and Biden not being replaced is PEBKAC, that involves a host of very different issues that you are only simplifying down to be similar in your head. For one, the change from Biden didn’t result in another foreign state, specially one that has experience and weight with influencing US and western institutions (AIPAC ring any bells?), trying to influence US elections, rather, it dismantled the efforts from the foreign state already involved in election manipulation that were singularly focused on Biden, forcing them into disarray.