Harrison, 27, was 18-11 with a 3.29 ERA in 32 starts last season (213 1/3 innings). He is arbitration-eligible for two more years and made $2.95 million last year.
"I like it here and want to be with this team," Harrison said. "We'll see how it goes. We're still talking."
Harrison said that if something isn't done before the season, he'd likely prefer to wait until after the season and talk again so it doesn't serve as a distraction. The Rangers inked Derek Holland and Ian Kinsler to long-term deals last spring, getting Holland done during spring training and Kinsler completed a few days after Opening Day.
Harrison has made at least 30 starts in two straight seasons, posting a 14-9 mark with a 3.39 ERA in 2011. So he's got two consistent seasons under his belt and goes into spring training as the likely No. 2 pitcher behind Yu Darvish.