It's the Big Three vs. the Suburban Six.
People searching for Election Night clues of who will be Minnesota's next governor can zoom in on just a few areas.
For Dayton, a former senator on his ninth statewide ballot counting primary elections, the keys are Hennepin, Ramsey and St. Louis counties. All three Democratic strongholds are a safe bet to wind up in his column, but his success will be measured by how wide a margin he rolls up there.
For Emmer, the six collar counties that wrap the Twin Cities urban core - Anoka, Carver, Dakota, Scott, Washington and Wright - are places the Delano lawmaker needs to pump up his numbers if he expects to win.
At least 2.1 million and as many as 2.3 million voters will cast ballots in Tuesday's election. This year is considered an off-year election because there isn't a Senate race or a presidential contest to drive up Minnesota turnout. The last comparable election was 1998, when 62 percent of eligible voters showed up, much higher than usual.
Since 1990 - the start of a Democratic losing streak in governor's races - the winner's vote total has ranged from about 774,000 to just shy of 1.1 million. The average winning tally is 958,000 votes.
Democrats have had better luck in Senate races, winning three of the last four.
Those Senate candidates have won by swamping their rivals in high-turnout precincts from Duluth to the Iron Range and in the Minneapolis-to-St. Paul corridor.
Sen. Amy Klobuchar had almost three times as many St. Louis County votes as Republican Mark Kennedy in 2006. Two years later, even in Democrat Al Franken's narrower-than-narrow win over Republican Sen. Norm Coleman, Franken rolled up 26,000 more votes in St. Louis County. In his last election a decade ago, Dayton doubled up on then-Sen. Rod Grams on his way to a victory.
While not as pronounced, Ramsey and Hennepin counties have delivered lopsided margins to Democrats for years. When that doesn't happen, it spells trouble for Democrats.
Take Mike Hatch, the Democratic nominee for governor in 2006. He attracted 70,000 fewer votes than fellow Democrat Klobuchar in Hennepin County in his loss to Republican Gov. Tim Pawlenty. Hatch was well behind Klobuchar's totals in Ramsey and St. Louis counties, too.
In his 2002 victory over Democrat Roger Moe and the Independence Party's Tim Penny, Pawlenty was unusually competitive for a Republican in Hennepin and Ramsey counties, losing Hennepin by a mere 3,000 votes.
Pawlenty was re-elected four years ago by a single percentage point.
Key to both Pawlenty victories were blowouts in the six counties that ring the Twin Cities. He built up a 125,871-vote cushion in those counties in 2002, about 70 percent of his victory margin. Four years later, Pawlenty's advantage in the six-pack was about 80,000 votes, which helped him hold off Hatch for a 21,000-vote statewide win.
Third-party candidates with strong left-of-center appeal have complicated life for Democrats in the past few races for governor. In 2010, the Independence Party's Tom Horner has more extensive right-of-center ties, gaining the endorsement of three former statewide GOP officeholders.
Horner has faded in recent polls and would need a late surge to pull off a win. But he figures to play a big role in the outcome no matter what.
Democratic strategists have said a Horner showing in the low-to-mid teens could help them, figuring he'd cut into Emmer's margins in the suburbs and portions of southern and western Minnesota precincts vital to GOP candidates.
Veteran Republicans hope to see Horner slip beneath 10 percent, hoping that most of his lost support will go to Emmer.
Brian Bakst has covered Minnesota politics for The Associated Press since 1999. He can be reached at bbakst(at)ap.org.
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