Posted: Thu Aug 21, 2008 3:37 pm-
You can't technically go from a TN to a K3, however, once you already have your TN, you can start the process for a K3 (or rather the CR1, which is the superior visa really, and processes in about the same amount of time, currently about 1 year for both actually thru Montreal).
Your TN will expire though before the K3 or CR1 is completed, so you'd have to leave the US and wait out the rest of the process, which will be a couple or few months, give or take. So if you really like your employer, you'd have to butter them up to allow you a leave of absence while you wait it out. Once an immigrant petition is in with your name on it, you wouldn't be able to renew your TN.
Your wife can sponsor you for either of the K3 or the CR1, (which both include the use of the I-130 petition, whether the US spouse is currently living inside or outside the US, doesn't matter) if she doesn't have any US income, you can get a co-sponsor. A co-sponsor can be ANY US citizen with income sufficient to support you. Doesn't have to be family, it can be a friend, or even complete stranger really, but I think that would be odd

Your wife would still be the primary sponsor, however the co-sponsor would then be taking on all the financial requirements, for a committment of 10 years.
Visa Journey is great. I've also BTDT with the whole spouse sponsorship thing, so I can answer almost anything immigration related (the process has changed a little bit in the past couple of years since I've been here, but its still basically all the same paperwork).
**edit to add**
actually, come to think of it, you can do Direct Consular Filing in Canada for the CR1 visa. Don't bother at all with the K3, it sucks. CR1 via DCF can be completed in probably less than half a year.
See the DCF forum at Visa Journey for info.
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