A birdie at the par-4 17th led to Fraser's three-round total of 8-under 211.
He began the round in a tie for fifth place and will attempt to bag his second tour win on Sunday at the longest course in European Tour history.
"Just keep plodding along -- that's all the mindset was," Fraser said a day before his 31st birthday. (Barseback) is a tough course."
Denmark's Jeppe Huldahl (70), England's Lee Slattery (75), the first-round leader, and Sweden's Martin Erlandsson (72) all are 7-under 212 and share second place, while second-round leader Ricardo Gonzalez (77) of Argentina is 6-under 213 and shares sixth with England's Marcus Higley (70).
Defending champion Peter Hanson (75) is tied with five others at 3-over 222 and in 56th place.
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