Blake Pedersen defeated two challengers to win the right to represent the PC party in the constituency of Medicine Hat.
Pedersen won the riding for the Wildrose in 2012, but last December he and eight other Wildrose caucus members crossed the floor to join Premier Jim Prentice and the PCs.
A total of 11 Wildrose members crossed the floor late last year.
One of them, Ian Donovan, has already been acclaimed as the candidate for the riding of Little Bow.
Two others are not running again while the rest, including former Wildrose leader Danielle Smith, are still battling it out to win their nominations.
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