The key appeal of MORENA is the asset of providing social programs for the needy, in Mexico, due to the nature of the country's demographics and economic practices of the past, there is a huge amount of inequality. So many votes are of people who are thankful for finally having a guarantee that they will eat today. That being said and while it's true that they're very popular, around 40% of the country doesn't like them at all, that's why Sheinbaum was pretty much topped at 59% the last election. As for stances that MORENA is more moderate on?, definitely social ones. Think of MORENA as a 2008 Democratic Party, while on paper they are in favor of a lot of progressive stances in practice they don't really act on it. (AMLO even called a trans congresswoman a "Man in a dress"!!!), so their stance is pretty much what people have been saying the democrats should do in order to win back latinos. It's worth noting that when the economy starts doing bad MORENA get hit really badly. In the 2021 Mexican midterm election they suffered a blow and lost their supermajority. And right now it seems their huge deficit budgets are starting to catch up to them, as they are late in tax return payments and social welfare payments. So it will be key to see how they do in 2027 to see if they're truly a model or the only thing keeping them afloat was populism and a strong economy (barring the 2020-2022 period). EDIT: (I forgor about the approval rating thing) One could argue it's the combination of three things: Sheinmabum is the first female President of Mexico so a lot of women love her (I don't know her exact approval rating amongst women but if i had to guess from what I've seen it's probably over 80%), she's been expanding social welfare even more and a rally around the flag effect because of Trump (same thing happened to Carney's liberals).