Methods of labeling and detecting a target nucleic acid by incubating a target nucleic acid with a terminal transferase to extend a terminus of the target nucleic acid and provide an extended region; hybridizing the extended region of the target nucleic acid with a template polynucleotide having a nucleotide sequence complementary to the extended region to obtain a hybridization product; and incubating the hybridization product with a nucleic acid polymerase and either a deoxynucleotide triphosphate (dNTP) having a detectable label or nucleotide triphosphate (NTP) having a detectable label to further extend the extended target nucleic acid.