Voters in Westchester and the Hudson Valley are headed to the polls Tuesday to vote in primary elections.The highest-profile race in Westchester features incumbent District Attorney Janet DiFiore being challenged for the Democratic nomination by Tony Castro.Westchester County Clerk Timothy Idioni is also facing a challenge for the Democratic nomination from Robert Morabito. Other elections include the races for the Democratic nominations for Ramapo town supervisor and mayor of Middletown.