Mystery Goose (or Swan)

This morning there were a couple of impostors mingling with the Canada geese.  I could not get any decent photos, but I watched them for a while through the binoculars.  I'm dying to find out what they are, but from what I have found, there are only a few different types of geese and swans in the US, and they don't look like any of them. 

There were two of them, the one circled in the back (obviously), and the arrow is pointing to another that is next to a Canada goose. 

These guys were a fair bit larger than the Canada geese, and as you can see, they looked a bit different from each other.  The white patches on the circled bird were more obvious than the photos suggests, and it had a white dorsal line down the back of the neck seen here:

They were both pretty motley looking around the beak, head, and neck.  One of them may have had some nobbly/wartiness around the beak, but it was hard to tell.

We are looking at the guy on the right. (He is looking right back at us)

Finally, when they took off (inspired by a huge flock of Great Cormorants), you can see, in this horrible photo, that this one (on the right) has white wingtips.  This is the one with the white patches and white stripe down the neck.  The bird on the left is a Cormorant.

Someone please tell me what they are!!!