Setting specific parties and people aside, that’s not what “the base” means. The base is the diehard supporters. Many an election has been won by taking a minority base and adding in people who are not supporters but chose that candidate for whatever specific reason, e.g. “the price of gas.”
He won with fewer votes than Biden got to win in 2020. And not all of those are his 'base'. Many probably didn't even know who Biden is, they just voted for the guy promising to lower prices.
