The lone survivor of a deadly 2007 home invasion in Cheshire is considering running for Congress.  Republican state Representative Dr William Petit is among a growing list of potential candidates eyeing the seat now held by Democrat Elizabeth Esty, who is under fire for her handling of harassment complaints in her office. She's not seeking re-election.  Petit is among at least five declared or potential 5th District candidates.  GOP State Senator Eric Berthel, whose district includes the Southbury area, is also considering a run for Congress.