Are you refering to "Consular Processing" meaning that the US citizen spouse sends the I-130 petition directly to a US consulate in Canada then? Not to a processing centre in the US?
If so, then that particular option is not available to this couple because they live in the US, not Canada.
In order for a couple to "consular process" as I think you're suggesting, the US citizen half *must* be a legal permanent resident In Canada. That is not the case for the OP, as they're in the US, her with a TN.
They're only option is to apply for Adjustment of Status, or have her return to Canada for about a year and petition and apply for an immigrant visa.
Here is the link to the
I-130 form the instructions on it have the address where to send an adjusment application.
Here is a
link to a site that details
Direct Consular Filing which clearly states that a US citizen needs to be permanent resident in Canada to be eligible to file from Canada.
U.S. citizens resident in Canada who wish to file I-130 petitions on behalf of their spouse, minor children or parents may do so at the U.S. Embassy or U.S. Consulate in whose district they reside. Please check with the specific consular officer for the filing requirements and procedures at that office. Some offices permit filings by mail. Many offices require filings in person by appointment only. In the latter case, both the petitioner and the beneficiary must appear in person at the time of filing.
And of course, the
www.visajourney.com website where there is more information and a message forum with other couples who've done various types of immigration to the US based on marriage.