An enhanced VSB transmitter includes a data attribute generator which generates data attribute information based on a current enhanced mode map, and a VSB pre-processor which codes first and second supplemental data for error correction, interleaves the coded supplemental data, and expands the interleaved data at first and second rates, respectively, according to the data attribute information. The transmitter further includes a multiplexer which multiplexes main data with the expanded supplemental data according to the data attribute information, and a VSB processor which codes the data multiplexed by the multiplexer for error correction.