Dozens of interviews with people deeply familiar or involved with the election process point to a clear consensus: Not only could Trump make a second attempt at overturning an election he loses, he and his allies are already laying the groundwork.
Archived at https://ghostarchive.org/archive/8e3Ri
Except that the Dems are consistently unwilling to play hardball. The generals would have to make the decision to intervene without being asked for that scenario to play out. I don’t know much about sentiment in the upper (or even lower) ranks of the US military, but that seems unlikely.
Even then, there’s a significant chance Harris refuses to be put in power by military intervention, or the generals believe she would remove them and instruct her attorney general to prosecute them. So military intervention, if successful, would at best mean new (military supervised) elections.