Three things come to mind. First, what have your temperatures been like? Pansies need daytime highs to be consistently below eighty degrees. Above eighty, and the stems elongate, giving the plants a spindly appearance. Cutting back helps their appearance but can dramatically slow down bloom production.

Second, your fertilizer may be the trouble. I have found that pansies much prefer organic fertilizers: fish emulsion, blood meal, bone meal, stuff like that. This is not to say that they will refuse to bloom with synthetics (though they can with some), but there is a very definite difference.

Finally, it's possible that you are watering too much. Pansies do not like to be too wet, especially if your soil has less than ideal drainage. I would strongly suggest that you stick your finger in the soil around your plants before watering. Rub your finger and thumb together. If you can feel moisture, do not water. For my plants at this time of year, once a week watering is just about right, but the only way to know is to give it the finger test.

Here is a link that might be useful: Pansy thread in Annuals Forum

Thanks so much for the very informative answer! I live in Georgia and the temps here are erratic at best. For example today its been a high of about 63 with the overnight around the 30's; 3 days ago it was 80 with a low of about 58 and we are expecting a return to that later on this week. its just crazy and unpredictable. Yet there isn't much to cut back. Each plant has compact foliage with maybe one or two floppy stems per plant.

I was wondering about my choice in fertilizer so when I head to the store next week I will definitely pick up something organic like you suggest.

Glad to know about the water situation becasue I've been so afraid that I wasn't watering enough! I've killed many a plant from lack of water. I'll ease up on the water now.
Thanks again for your help.

When I put mine in..usually in October so the roots get established first, I pinch off all the buds and flowers because where they're grown(in a greenhouse) they are much closer together and with brighter,longer light than you are giving them.
These greenhouse blossoms are on longer stems so pinch them off and let the foliage mature so it can support these bigger blossoms to come later.

@dottie I didn't consider that. I planted mine mid October and did some light deadheading along the way but didn't pinch off all of them. How long does it usually take for the bigger blossoms to come in after pinching off all the flowers?

Fertiloam makes a wonderful pansy food...I swear by it. Since you're in zone 8 I suggest you feed them lighty once a month all winter long.