By Moira Warburton WASHINGTON (Reuters) – A group of U.S. Senate Democrats sounded the alarm over a lack of election workers ahead of the Nov. 8 midterm voting, citing threats and harassment as hurdles to recruiting crucial staff. In an Oct. 6 letter to the U.S. Election Assistance Commission, 13 Senate Democrats and two independents aligned with Democrats called for the federal agency to step up efforts to support states in recruiting workers needed to run next month’s midterm elections. Voters will cast ballots across the United States in races for Congress, governor and many other state and…