MINNEAPOLIS (WCCO) — We are a little over a month away from the August primary and one of the most competitive races is the DFL battle for Minnesota governor.

Three candidates with a history of winning elections are facing off: Minnesota Rep. Erin Murphy, Attorney General Lori Swanson and U.S. Rep. Tim Walz.

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The race will likely be decided by an unpredictable factor — voter turnout.

Traditionally turnout in Minnesota’s mid-August primary runs a pretty low 10 to 15 percent. But with key races at stake turnout this Aug. 14 could be closer to or even surpass 20 percent.

In a surprise, Murphy locked up the endorsement at the June convention. She was so excited by the win she literally did a victory dance.

Walz was second at the convention, but the DFL contest was upended when, on the day before the filing deadline, Swanson jumped into the race.

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Swanson’s pick for Lieutenant Governor was also unexpected: 8th District congressman Rick Nolan, who had earlier in the year announced he was retiring.

Nolan is expected to deliver critical votes in Northern Minnesota and Duluth for the Swanson ticket. DFL-endorsed candidate Murphy, who is from St. Paul, chose as her running mate Rep. Erin Maye Quade, from Apple Valley. That means the “all Erin” ticket is also an all-metro ticket.

“In the last election an all-metro ticket did win — Gov. Dayton and Tina Smith,” Murphy told Esme Murphy on WCCO Sunday Morning. “But that is not really the point. The point in an election is what you are going to do for the people of Minnesota.”

Walz, who is from Mankato, chose Minnesota Rep. Peggy Flanagan, who is from St. Louis Park, as his running mate.

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The Republican match-up for governor is also expected to attract a lot of primary voters. Party-endorsed candidate Jeff Johnson is facing off against former two-term governor Tim Pawlenty.

Esme Murphy