The Blues are now 12 points behind sixth-placed Wycombe with seven matches remaining.
Admittedly, they still have two games in hand on the majority of the clubs involved in pursuing the play-offs.
Yet even then their chances appear doomed, despite Pompey losing one of their last 11 League One fixtures.
Nonetheless, Cowley is belligerently refusing to throw in the towel.
He told The News: ‘I’ll let you concentrate on the outcomes, my energy is in the process and trying to keep improving the performance – and I liked us tonight.
‘I am the optimist, I believe anything is possible.
‘I have managed in eight of the top nine divisions. When I was managing Concord Rangers in the Essex Senior League, no-one would have expected me to get to the Championship – but I did.
‘I’ll let everyone else be pessimistic, I’m going to keep going.’
Aiden O’Brien opened the scoring on 50 minutes, converting Marcus Harness pull-back for his fourth goal in 10 games.
However, Kieran Sadlier’s penalty 14 minutes from time earned the Trotters a point, following Hayden Carter’s foul on substitute Elias Kachunga.
Cowley added: ‘We went there to try to win the match – and I felt we did enough to do that.
‘We had a really good place in the game at 1-0 up and had numerous moments in that period where we’ve just got to be clinical and more ruthless.
‘But our play up to the final action was very good against a good Bolton team, who are very well-coached in possession.’
A message from the Editor, Mark Waldron
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