Comprehensive Recommendation
If you are looking for efficiency and comfort, I recommend flying directly from Mexico City to Chicago O'Hare International Airport with Aeroméxico or United Airlines. This option offers the best travel time, taking about 6 hours 15 minutes, and total estimated costs of around R12,000 - R15,500.
However, if you prefer a more scenic route or are on a budget, consider taking a bus with Greyhound for approximately R3,000 - R5,500, but be prepared for a longer travel duration of around 26 hours.