The Greek striker scored a late header to allow the Hoops to win 3-2 at Spartak Moscow in their second Group G fixture.
The victory sees Celtic sitting second on the table on four points behind group favourites Barcelona and Samaras suggests that the Glasgow giants are now capable of progressing to the knockout phase after coming through the qualifying stages.
"We are already successful because we have reached our target," said Samaras.
"Our target was to reach the group stages of the Champions League and we did that by beating two really good teams in Helsinki and Helsingborgs.
"Benfica and Barcelona play in the Champions League every year and Spartak Moscow are in it most years, so it is not easy, but we have the chance to be competitive now and we want to win the games.
"All games are 50/50, so if we take our chances, you never know what will happen in football.
"It will be difficult to beat Barcelona or to get a draw with them but even if that doesn't happen we will fight for second position.
"And if that doesn't come then we mustn't forget that third position gets you into the Europa League. It is so good to have European football and even better to have it after Christmas."