Trump did lose in three states where the polls had him winning, it seems. Saturday will be more telling. Cruz has won three of the four closed primaries held so far. IF that holds true Saturday, he will pick up 3 states to Trump’s 1. At that point, I would say it is close.
Trump has about 25.5% of the delegates for the nomination.
Cruz has about 18.3% of the delegates for the nomination.
Granted, it would be a major upset if Cruz won 3/4 of the delegates. Probably the second place winner will be within a couple delegates of the winner. In fact, as Maine will likely split between Trump and Rubio, Cruz could win three of four states and come in third in delegates.
The average of polls for Saturday five primaries shows Trump up an average 35 to 20 for Rubio. I doubt it will change.