CV 251 then AA 1503 at O'Hare
Anchorage → Chicago → Cancún
Timetable, Chicago time
19:00CV 251 from Anchorage at the gate
08:25AA 1503 to Cancún leaves the gate
13 h 25 apart on the timetable, overnight
AA 1503 leaves 13 h 25 after CV 251 arrives on the timetable: more than half a day, so not a connection we count.