With two incumbents leaving office, there will be races for two seats on the ballot in Topsfield’s April 30 annual town election. With Paula Burke not seeking reelection as town clerk, there is a race between assistant treasurer Ann Gill and Catherine Granata for that position. There is one other race on the ballot, as Mark Frampton and Brian Rossano are running for the one-year unexpired term on the Park and Cemetery Commission most recently held by Michael Smerczynski. The election will be held in conjunction with the special state primary to fill the US Senate seat formerly held by John Kerry. The final day to register to vote is April 10, when the town clerk’s office will be open until 8 p.m.