The process to file for your fiancee as a K-1 which is generally considered the fastest process is below. You can anticipate 6 to 8 months for the process.
Filing the K-1
Step 1) You would file the 129-F with USCIS. USCIS.gov and click forms.
Step 2) After the petition is approved, your fiancee would fill out the forms sent to her
by the National Visa Center.
Step 3) You fiancee would be interviewed at the nearest US consulate in Brazil.
Step 4) You fiancee would enter the US.
Key Points to remember would be that you and you fiancee would need to be married within 90 days of her arrival to the US and she would need to adjust status to a lawful permanent resident within those 90 days using Form I-485 or be required to return to Brazil.
The eligibility criteria is fairly simple:
a) U.S. citizen spouse
b) Both parties are free to marry
c)genuine intent to marry upon arrival to the US
d)both parties must have met and seen each other in person within the
last two years.
Technically, your fiancee is still eligible to apply for a tourist visa while the K-1 is pending
although it may be more difficult to be approved as many US consulate officers will assume immigrant intent even if your fiancee only requests a short trip to the US.
Edited by Wilton A. Person on 8/19/2010 at 8:37 PM EST