What Kind of Sandpiper?

I was up in Secaucus on Friday afternoon and I stumbled upon these sandpipers as I was on my way back to the meeting I was attending. I thought they were spotted sandpipers (although I was suprised to see more than two at once—there were six of them in a little flock), and now that I examine the pictures, they don't seem quite right for spotted sandpipers.



I don't have a good front-on picture, so it's hard to tell what the markings are on the birds' chests. This one looks a little more like a spotted sandpiper, but I'm thinking that perhaps these are least sandpipers.



What do you think?