From Longman Dictionary of Contemporary Englishpick a winnerpick a winnerinformalCHOOSE to choose someone or something very good → pick
Examples from the Corpus
pick a winner• Experience to date and motivational goal data give us our greatest chance of picking a winner.• A technology Strategy does not mean that a government has to pick winners and losers.• Trust you, Dwight, to pick a winner, and pick him before the rest of us have heard of him!• Softbank claims that it is better at picking winners and that it is buying into a growth industry.• The government hopes to pick a winner in May but the selection could be delayed. 