I hesitate to lay a specific ID on a clematis unless it is patently obvious because there are just too many that look so similar. But if it's blooming now, it's a pruning group 2 clem, if that helps you out :-)

It is blooming now, but so is my Ville de Lyon and my Pink Fantasy which are #3's

Well then, I don't know what to tell you :-) Typically group 3's are labeled "late blooming" and usually don't start flowering until midsummer (late June or July) while type 2's ("early blooming") start in late spring, typically pause for a month or two then produce a light, late flush. That used to be the guideline on determining how to prune if you had an unknown variety - the timing of the bloom cycle. And they certainly still seem to follow that pattern in my climate. My type 2's are blooming now but none of my type 3's (most of my collection) have started to produce flowers.

To attempt an ID, I'd suggest you follow NHBab's good advice on another post and check out the search feature available on Clematis on the Web. Just put in all the attributes of the vine in question (# and color of tepals, stamen color, size, etc.) and see what turns up.

My guess is Earnest Markham clematis.

What zone are you?