NCR already beat the enclave and sent them into a full retreat. They also beat the brotherhood’s central chapters. The tough one to gauge here is the master’s army as that’s a steadily expanding force. At the start of FO1, easily. By the end... more difficult to say. That would likely be the most challenging fight on this list for an NCR at least post-fallout 2.
NCR, It’s the closest we have to a real America and is quite powerful (if the soliders didn’t want to die so much), democratic and not Totalitarian like legion but it has taxes, but hey it has no racism (I think)
or
Legion, more or less so a massive militia than a actual state due to it have little to none civilian population, a military force to match NCR in strength even beating them in some battles, but extremely dictatorial, totalitarian, and cares littles for other states
^^^The legion does have a civilization. We don’t see their heartland or their formal territory in NV, we see their frontier and forward camps. We know from trader dialogue that they have settlements and civilian regions, even trade networks and highways. I mean, you’d have to to run an area comprising territory in 6+ states. However it is true it’s not a very GOOD civilization. Slavery and lunatic punishments over minor crimes are everywhere.
If Institute is at end game they have a fair chance of winning with their ability to produce a seemingly infinite army and many synths at every military check point in the entire commonwealth. Not to mention that unless other factions find out where they are they're basically unbeatable.
