United Airlines has a $40.10 one way fare between Los Angeles and Chicago on about a dozen dates in March to May. This seems to be undercutting low fares from Frontier and Spirit Airlines. Tuesday, Wednesday and Saturday flights. There are options for $80.20 round trip tickets for one day, three or four days and longer trips. The low fares out of LAX look like only red-eye flights.
United Airlines Los Angeles LAX – Chicago ORD
$80.20 Tuesday April 19 – Saturday April 23
Since this fare only earns 260 redeemable miles in United Mileage Plus for the non-elite flyer, you can check out http://wheretocredit.com/ua/n for other Star Alliance carriers who will give you 50% miles credit to earn 1,745 redeemable miles on this $80 round trip United ticket.