A method and apparatus for delivering interactive television (ITV) data by using the same TV scan line that also carries closed caption data. The ITV data is inserted into the scan line with CC data by detecting a gap associated with a first CC data unit. If the gap is large enough to contain all of the group of ITV data units then electronically insert the entire group of ITV data units into the gap. If the gap is not large enough to contain the entire group of ITV data units, insert a subset of the entire group of the ITV data units into the gap and continue to the gaps associated with successive CC data units, inserting subsets of the ITV data into subsequent gaps until the entire ITV message has been inserted into the gaps between CC data units.