I think a picture would really help.

Hi,
Maybe you have a Mahonia. They look like hollies, turn dark red in the winter, and bloom in the spring with yellow flowers.
Remy

Here is a link that might be useful: Google Images of Mahonias Blooming

The closeup of mahonia flowers looked similar, but my flowers are in clusters, not the long spikes pictured. Mine is growing and blooming in pretty deep shade, so it probably wouldn't photograph well. Also it does not turn dark red in winter. The leaves either stay green or (the upper and outer ones) turn brown.

Thank you for putting me on the right trail. I found an image of Mahonia aquifolium which is exactly my shrub. I am surprised because it is only hardy to zone 6 or 7, but we have all seen "Zone Denial" in plants and people.