By the numbers: The dip in Dayton's approval ratings

According to the latest SurveyUSA poll, DFL Gov. Mark Dayton's approval ratings have dipped significantly since last year.

The recently released numbers from the organization, which works with KSTP-TV in Minnesota, show that the governor has an approval rating of 47 percent. That's down two percentage points from the organization's poll earlier this year, a change that is within the margin of sampling error. The SurveyUSA polls on Dayton's approval ratings have had a margin of error between 4.3 percentage point and 4.5 percentage points, plus or minus.

Significantly, however, the September approval rating is down 9 percentage points since May of 2012. Back then, when Dayton was still grappling with a Republican controlled Legislature, the governor's approval rating was 56 percent in the SurveyUSA poll.

The dip was particularly glaring among Democrats:

According to the SurveyUSA poll, Dayton went from an 80 percent approval rating among self-identified Democrats in May of last year and February of this year to 67 percent approval rating. The pollster said that segment of the poll had a plus or minus 6.7 percentage point margin of sampling error.

The Star Tribune's polling over the past two years do not track with the SurveyUSA polling. The latest Minnesota Poll, which had a margin of sampling error ofplu sor minus 3.5 percentage points, was taken in June and found Dayton's approval rating was 57 percent. That was up from 45 percent in February of this year and 53 percent in September of last year in Star Tribune polling numbers.

A key difference: In the Star Tribune's June poll almost all self-identified Democrats said they approved of the job Dayton was doing. According to that poll, 89 percent of DFLers gave him high marks. Similarly, in February, when fewer than half of those polled said that they approved of the governor's job performance, Democrats still stuck by him with 82 percent of DFLers giving him approving marks.

What does it matter? Potentially losing ground among his party members would be a major blow to the governor, who will need their support as he vies for re-election next year. Dayton, who won his first election with just 42 percent of the vote, will need the states DFLers to stick by him to best his Republican challengers. Further, if a significant chuck of Democrats are turning against the Dayton agenda, DFL voters would become less likely to vote to continue DFL control of the Minnesota House.