Electrical connectors having leadframes

An electrical connector includes a contact module having a leadframe and a dielectric frame surrounding the leadframe. The leadframe has signal conductors having transition contacts encased in the dielectric frame. The transition contacts are coplanar such that the transition contacts are arranged within a contact plane of the leadframe. The signal conductors have mating contacts extending from the corresponding transition contacts. Each of the mating contacts have a mating interface configured to be electrically connected to a corresponding mating contact of a mating connector. The mating contacts are arranged in pairs with the corresponding mating interfaces aligned in rows along corresponding row axes. Each of the pairs of mating contacts are arranged in different rows.