The chairman of the Republican Party in Indiana’s 4th legislative district has been sworn in as the newest member of the state Senate.Peter Miller was chosen to fill the seat formerly held by Secretary of State Connie Lawson.Republicans in the district west of Indianapolis still need to select a candidate to replace Lawson on the general election ballot.Governor Mitch Daniels chose Lawson to serve out the term of former Secretary of State Charlie White, who was forced out of office following his convictions on vote fraud and other charges.