Not everyone in the Arab world looks favorably upon Palestine. They don’t care that Trump plans to escalate the genocide.
A lot of them are socially/fiscally conservative. Just because the Republicans lean overwhelmingly Christian doesn’t mean that their values differ entirely from Islam. Anyone who hates abortion, gay/trans people, and wants to keep drugs criminalized will be more inclined to vote Republican despite the widespread islamophobia.
The anti-Biden campaign, which is taking advantage of the Israel-Palestine conflict, has been successful at convincing voters, even if they are unwittingly voting against their own self-interest. The Republicans are good at that, such as how effectively they sway members of the working class towards supporting rich oligarchs and racial minorities to vote for racist candidates.