The most honest answer is "maybe". As stated above, a 15A circuit will have #14 wire, which can carry the load. The question is how far is your receptacle from the breaker/panel? It could be 20 feet or 75 feet. Your biggest enemy is voltage drop.
The only way to be sure is to plug in and run it. Measure the voltage inside the trailer. If it's less than 112 volts I say shut it off. I know others will say 110 or even 108 but that is too low for my comfort. The bottom line is MEASURE.
Of course, if the breaker won't stay closed it doesn't matter.