Rubio should get out BEFORE Florida. Florida's primary is on 3/15, a day on which six winner take all primary elections are held. If he's in the race on 3/15, he'll end up handing hundreds of delegates to Trump needlessly.
OK, I'll try my hand at predicting the front-runner in these races:
Saturday, March 5 -- 155 Delegates Total
Kansas........40 Delegates, Proportional, Closed Caucus Cruz
Kentucky......46 Delegates, Proportional, Closed Caucus Cruz
Louisiana.....46 Delegates, Proportional, Closed Primary Cruz
Maine.........23 Delegates, Proportional, Closed Caucus Trump
Sunday, March 6 -- 23 Delegates Total
Puerto Rico........23 Delegates, Proportional, Open Primary Rubio (?)
Tuesday, March 8 -- 150 Delegates Total
Hawaii........19 Delegates, Proportional, Closed Caucus Trump (?)
Idaho.........32 Delegates, Proportional, Closed Primary Cruz
Michigan......59 Delegates, Proportional, Closed Primary Trump (?)
Mississippi...40 Delegates, Proportional, Open Primary Trump
Thursday, March 10 -- 9 Delegates Total
Virgin Islands..9 Delegates, Winner Take All, Open Caucus Trump (?)
Saturday, March 12 -- 57 Delegates Total
Wash. DC......19 Delegates, Proportional, Closed Convention Trump
Guam...........9 Delegates, Unbound, Closed Convention Trump (?)
Wyoming.......29 Delegates, Unbound, Closed Caucus Cruz
Trump will end up on 3/12 with the most delegates though Cruz-Rubio combined will likely have about 100 more delegates than Trump. Just my guess.