Two Dark Lords?

[Boromir88]

I think Boromir was the victim of deluisons of granduer. Isildur himself, at least, had wisdom in the end.~Inziladun

But this wasn't something just seen in Boromir, the delusions of grand power was the trademark of the Ring. That was how it deceived:

In the “Mirror of Galadriel”, I 381, it appears that Galadriel conceived of herself as capable of wielding the Ring and supplanting the Dark Lord. If so, so also were the other guardians of the Three, especially Elrond. But this is another matter. It was part of the essential deceit of the Ring to fill minds with imaginations of supreme power. But this the Great had well considered and had rejected, as is seen in Elrond’s words at the Council. Galadriel’s rejection of the temptation was founded upon previous thought and resolve.~Letter 246

All the Bearers were tempted with the idea of using the Ring to overthrow Sauron (so where do they get off scolding Boromir! ) The difference is of course, they rejected this path, Boromir never did and I doubt he ever wanted to.

With someone like Boromir's character, this makes him more susceptible to the Ring, than say Hobbits, or even of other men. In a way you could say his personality pre-disposed him to the Ring's temptation. However, the Ring plays the same old trick with everyone, tempt them with delusions of supreme power. It may have been less noticeable in other characters like Sam and Gollum, but the same deceipts were there. Gollum even has visions of using the Ring to exact revenge on everyone of the nasty people who did him wrong and he could be the great lord, feasting on all the fish he wants. Sam has his vision of leading an army against Sauron and restoring the Gorgorth into a garden.

This is the trick of the Ring, Boromir may have been more susceptible, but his visions of granduer are not unique.

Bombadil seems to be an exception, but as noted he's a completely different character. This is simply my opinion, there's no way to 'prove' it, but for what it's worth. Bombadil says he is his own master, and Gandalf suggests in the Council that Bombadil would most likely lose the Ring for he would not care. Bombadil has a laissez faire attitude to all of Middle-earth, the only thing he cares about is what he is in control over. Simply put, the Ring has nothing to work with, Bombadil is his own master and doesn't care about Sauron or what he does. He is present in Middle-earth, but at the same time not completely in it (he's just not all there ).

All the other characters in the story have something at risk, and Sauron threatens to take it, so the Ring uses its tricks to offer them the power to defeat the Dark Lord they want to see destroyed.