Various responses I have gotten:

Looks like a Golden to me. Even at this angle you can see how long the primary wing tips extend from tertial feathers. Dark cap is obvious as well. Nice photo! I could be wrong but I don't think so. Sometimes a Black-bellied will throw me off here in Northfield, just as a Golden would you on the shoreline. Not their typical habitat.
These two can be hard to tell apart, but this bird is most likely a Black-bellied. A Golden would be darker and the bill is too large to be a Golden's, at least from what I see.
I believe it is a juvenile Black-bellied Plover by virtue of the overall size, and the streaked neck as seen in the photo. The juvenile BBP as a juvenile in Sibley shows a pale cap and your bird definetly shows a streaked cap but to me the bill is too large to be a Golden
Yup, American Golden Plover
After studying a Sibley guide for a few minutes, my guess is you're right that it's an American Golden-Plover - but that's only a guess. A key question is, did you get a look at the underside of the wings? Black-Bellied would have black axillaries ("wingpits"), and Sibley says Black-Bellied has white underwings, while Golden has grayish underwings.
My vote is that the bird is indeed an American Golden-Plover. For me the most important mark is the dark crown with the many, small golden flecks. Black-bellies do not have dark crowns, Goldens always have them. Also note the golden flecking on the back. Although difficult to discern in this photo (the bird is turned the wrong way), it does give the impression that it is darker on the breast and belly than a Black-bellied (another very good mark in the off-season). The only thing not going in its favor is that the bill appears a bit long for a golden. However, I still believe it is a golden. The legs are very long, which might even get someone to think that this is ANOTHER of the golden-plover species, e.g., Pacific Golden-Plover.
Golden. Also skinnier neck, darker crown, and smaller bill than BBPL.
I'm not expert, but look at the picture and notice the head glowing gold in the sunlight! And it looks to be a lot "finer" bird than the chunky black-bellied
I'm especially interested in the majority opinion about your plover photo--I saw my life American golden plover yesterday at Plum Island (molting, but mostly in breeding plumage.) I'm the first to admit I'm a befuddled novice with shorebirds. I'm wondering if this is either a young or winter-plumaged black-bellied plover. To me, the beak looks a bit heavy and the outer primaries extending over the tail look very dark. I agree about the prominent light eyebrow, though. ???
To me, this bird looks too large-billed to be a Golden Plover. It also seems to lack warm golden-brown tones. I'd guess that it's an immature, hatch-year Black-bellied Plover.
[but later, same person]
Hi again, Having looked at some pictures online, I'm a lot less sure than I was five minutes ago. :) It does indeed seem to have a strong white superciliary, and bill doesn't seem as large as some online Black Belly bills.
The supercilium, dark crown and maybe more, the long dark wings beyond the tail look like a golden to me.
Looks like you have a juvenile American Golden-Plover here. A darker & smaller-headed bird than the Black-bellied, upperparts are heavily spangled (speckled looking in these plumages). White supercilium quite evident. Underparts appear to be heavily barred or streaked (at least from what I can tell from the angle of your photo). The barring (at least on the flanks) continues well beyond the legs (streaking on immature Black-bellied generally stops at the legs). Long wings & primary projection also evident.