** Brokerage Jefferies upgrades energy utility co One Gas OGS.N to "buy" from "hold" and raises PT to $84 from $76

** New PT represents a 14% upside to stock's last close

** Brokerage believes OGS is a defensive utility company that can perform well in uncertain economic times

** Brokerage sees upside to company's unique financing structure, potentially boosting earnings if interest rates are cut

** Lower natural gas prices could help improve outlook for OGS customers, says brokerage

** 3 of 9 brokerages rate stock "buy" or higher, 5 rate hold, 1 rates "sell"; their median PT is $75.5 - according to data compiled by LSEG

** As of last close, OGS up 6.3% YTD

(Reporting by Padmanabhan Ananthan)

((Padmanabhan.Ananthan@thomsonreuters.com))