The argument is that Elon’s purchase of Twitter was essentially to influence the elections.

I’m not sure how true that is, but it’s certainly possible and he’s definitely acting like it.

Wouldn't it have been cheaper to put all that money in a SuperPAC?

Do you think "lack of money" is one of the reasons that would make Trump lose?

It's not an unrealistic observation given that Twitter generates over half of its income in the US and almost a third of its daily active users is American. (https://www.statista.com/statistics/242606/number-of-active-...). The app is quite small and geographically centralized, with about 200 million daily active users. If its popularity in the US drops off with the already strained advertiser situation twitter is probably going to be in some trouble.