Directly dropping it would take a constitutional rewrite. Since the radical right controls a majority of state legislatures, you would not like the results of any constitutional convention. Besides the Compact described by Annette, there is another option: Remove the limit on the size of the House of Representatives. It was capped in 1929, by law, to limit the power of the growing cities and the immigrants in them. Dump that cap. Once the House is truly proportional to population, the electoral college will be also, with a slight modifying effect due to the Senate. Also, grant statehood to D.C.