How can I get my contacts to sync to my iMac properly?

Question

I have Contacts on my iPhone looking perfect. Some are from or linked to Facebook, some not, but they are all set to sync with iCloud. This works well, except on my iMac where the contacts are a bit different. For example, there are entries in the iMac Contacts app that aren't on my iPhone.
The bottom line is: I want to wipe out my iMac contacts and replace it with what's on my iPhone and keep them forever locked in step thereafter.
Help appreciated!
Celebrus

Answer 1

This turned out pretty poorly. Probably my fault– and in my opinion Apple's for making this such a nightmare.
Here's what I did:
1. Skipped this step
2. The contacts look right on iCloud.com, however none of the Facebook friends show up there and I'm not sure if they're even linked to Facebook data. Nevertheless, I created the vCard for everyone there.
3. I disabled Contacts sync in the iCloud preference pane. It asked do I want to keep contacts on the mac or remove them. I thought it wouldn't matter, so I just said keep. After that, the number of contacts on my iMac increased to 299. No idea.
4. I decided to back up a vCard for my iMac contacts as well. Then I deleted them all. Funny thing is– somehow iCloud Contacts sync had re-enabled itself. Down to 70 contacts on my iPhone.
5. I imported the iCloud.com vCard
6. I re-enabled Contacts sync and nothing happened. I had to drag all the contacts into the "All iCloud" group before everything reappeared.
At this stage, I now have 300 contacts on my iMac, 294 on my iPhone and 293 on iCloud.com. I have not yet investigated or reconciled this.
As a test sample, I reexamined the situation with my brother and father. On the iMac, iPhone and iCloud, there is now just one entry for each. However, my brother's Facebook data is now linked to my Dad's card. (If you'll recall, the iPhone was originally correct while the iMac had my father's iCloud data linked to my brother's card.) Amusing if it weren't so gosh darn aggravating.
More disconcertingly, many of my contacts on the iPhone which had been linked with Facebook are no longer linked. I tried relinking one, at which point, it looked correct, except the iPhone has this one contact linked to iCloud twice. It might be easier to delete everything and just go door to door to each of my contacts.
EDIT: And after I copied the data over from one of the two iCloud cards for that contact to the other, I deleted one of the iCloud cards. The remaining one has all the info, but that person's card has completely disappeared from the iMac.