Yes a sewing machine will punch evenly spaced holes but probably not as widely spaced as you'd like and probably not as visable as you'd like either

I have done this often on material. Use a metal crochet hook with a sharp end and simply punch through the material. I really don't know if they sell them any more, mine were my grandmothers and I've had them for many years.

You could try this. First sew a 1/4 inch hem. With fleece you'd only have to turn it down once because it doesn't fray. This would serve 2 purposes. It would give you a straight line so you know how deep to take your single crochet and enclose the raw cut end and give you a smooth end to crochet over.

Then you could try a large darning needle to punch through, then enlarge it by passing a skewer through the hole. Do only one side at a time because the holes tend to close in with handling. If you have a cutting mat use it. It has the 1/4 inches marked on it. If not use graph paper(You can get it and print it on line.), pin it on and punch through paper and material. Then remove the paper and enlarge your holes. Use the finer or midweight baby yarn to crochet.

If all this sounds like too much trouble, then do your edging and sew it on with a blanket stitch.

http://www.nancysnotions.com/product/supplies/handy+notions/edge+perfect+blade.do?search=basic&keyword=rotary&sortby=newArrivals&page=1

Use a hemstitching needle in the machine without thread, on the longest stitch your machine makes. If you have a basting stitch, use that. Hemstitcing needles are available in any sewing notions department.

Sherry

They have a blade for a rotary cutter called a Skip Stitch Cutter, maybe mention above, sorry do not have time to look up the above site.
Demo on site listed below.

Here is a link that might be useful: Crochet Hole Cutter

If you have any old tractor-feed style printer paper, you can use the spacing of the holes on the tear-off sides to determine your spacing on the blanket.

Helene