MINNEAPOLIS  — A Star Tribune Minnesota Poll published Sunday found that Democrats Mark Dayton and Margaret Anderson Kelliher lead Republican Tom Emmer in the race for governor.

The third Democrat running in next week’s DFL primary, Matt Entenza, also led Emmer but his advantage is within the poll’s margin of error.

In polling between the three Democrats running in the Aug. 10 primary, Dayton led Kelliher but not outside the large margin of error for an election expected to draw small voter turnout, and Entenza was third.

In the general election matchups, endorsed Independence Party candidate Tom Horner ran a distant third in all three cases. The poll also showed large numbers of voters still remain undecided in all three potential races.

The polling of general election matchups included 902 Minnesota adults and was taken July 26-29. For the first time, the polling included cell phone users, and has a margin of sampling error of plus or minus 4.3 percentage points. The margin of error in the smaller subset of primary voters was plus or minus 7.8 percentage points. The poll was conducted by Princeton Survey Research Associates International.

Kelliher, the Minnesota House speaker, is the endorsed DFL candidate. Dayton is a former U.S. senator and department store heir, and Entenza is a former prosecutor and House minority leader. Emmer is an attorney and state representative from Delano who faces no serious opposition in the Republican primary. Horner is a former Republican consultant and PR executive who is facing a challenge in the Independence Party primary from publisher Rob Hahn.

In the poll’s matchup between Dayton and Emmer, Dayton scored 40 percent support to Emmer’s 30 percent and Horner’s 13 percent, with 17 percent undecided. In a Kelliher-Emmer face-off, Kelliher was supported by 38 percent to Emmer’s 29 percent and Horner’s 13 percent, with 18 percent undecided. Entenza got 36 percent support to Emmer’s 31 percent and Horner’s 15 percent, with 17 percent undecided.

In the DFL primary polling, Dayton got 40 percent, Kelliher 30 percent and Entenza 13 percent.

In the general election contests, the Democratic candidates appeared to hold particularly wide leads among women and people older than 45, a gap that widened even further among those over 65. Emmer’s only identifiable strengths were among people who earn more than $75,000 a year and among Minnesotans between age 35 and 44.