I was studying these birds for a few moments in a mixed flock of House Finches and Goldfinches. These birds were sort of a blend of both. Light bulb moment! These are Pine Siskins, I hadn't see them in a few years.
There were about 40 of them at Massabesic. I know they irrupt every few years or so.
They were attacking the free seeds at the feeders. They don't blow me away by their beauty, but I was happy to see them. I have gone many Winters without seeing any, and any new birds are welcome on a late Winter walk.