The Latics are second bottom of the standings, above only QPR with 19 points, but Martinez, who has engineered Wigan's top-flight survival in the closing stages of the last two seasons, thinks this year will see a much tighter finish.
Historically, a 40-point target has been enough to secure Premier League status, but the Spaniard predicts that total could be a lot lower this year, with more teams fighting it out at the bottom.
Newcastle and Aston Villa are two sides hovering just above the relegation zone, while Fulham, Norwich and Southampton have by no means pulled clear.
"You look at the numbers and until you reach 40 points you haven't achieved your aim," Martinez said ahead of Tuesday night's clash with Stoke.
"You're looking at anyone from the 12th position down. It's going to be a really tight fight because you're looking at teams that are taking a bit of time to adapt to the division now they're ready, the newly promoted sides. It's going to be a very close final third of the season.
"Historically, 40 points is a measure of safety, but it could be a lot less than that. It's going to be a close fight because I do see teams that started at their best, but now they're not in a great position and others are beginning to find it difficult even though they are in a good position in the table.
"It's really open, probably more open than the table could suggest at this time."
Wigan travel to Stoke following their FA Cup win against Macclesfield before they host Southampton on Saturday.