Democratic candidate Janet Mills attempted to lay claim Tuesday to a key issue in the four-way race for governor — the economy. She presented a range of initiatives designed to encourage small business growth while addressing Maine’s dearth of skilled workers and its aging labor pool. Mills unveiled her economic plan amid the din of milling machines and compressors at Kennebec Technologies in Augusta, a precision-manufacturing company that does contract work for the Department of Defense. Her proposal includes overhauling and consolidating the state’s sprawling and confusing economic development bureaucracy, providing no-interest loans to businesses that hire more employees, rural workplace grants that convert abandoned downtown buildings into shared workspaces for companies and workers looking for high-speed internet access, and tax incentives designed to repatriate Maine workers who have left the state seeking better jobs and higher wages. Mills said the proposal targets the state’s economic weaknesses, but it also takes aim at what her campaign hopes is a key deficiency for her leading rival in the governor’s race, Republican Shawn Moody. “Why would we want to continue to do things the same way we have been and expect any results?