Here’s the math facing the DFL in its quest to retake control of the Minnesota House: gain 11 seats currently controlled by the GOP while holding on to all the seats currently held by Democrats. Republicans, with a twenty-seat margin, are on defense, but could mitigate the loss of some seats by flipping other blue seats to red.

Technically, all 134 seats are on the ballot in November, but the partisan leans of many districts make the election result almost a foregone conclusion. So where do Democrats and their allies hope to make their gains? And where are Republicans firing back?

Data released last week by the Minnesota Campaign Finance and Public Disclosure Board on spending by outside political groups — think big hitters like the Minnesota Jobs Coalition — and party-affiliated political spending committees gives a glimpse of where the parties are concentrating their efforts.

If these early reports are any indication, the contest for control of the Minnesota House in 2018 is looking like the battle of the ’burbs.

Spending rings the metro

The charts below visualize the money spent by outside groups and parties on House races so far. (Since each district is worth the same to parties in terms of controlling the House, each district is represented by a square of the same size. The squares are arranged to roughly correspond to the districts’ actual geographical locations.) For clarity, MinnPost has combined expenditures that benefit one party, either by supporting the party’s candidate or attacking her opponent, into a party total.

Those dark rings around the edges of the Metro side of the charts? That’s both parties targeting the suburbs, spending in races from Woodbury to Wayzata and Blaine to Apple Valley.

Here’s spending by outside expenditure groups to benefit Republicans:

Here’s the same data for groups spending to boost DFLers:

Something to note: while the GOP mostly relies on independent outside groups for spending in House races, the DFL tends to make use of party-affiliated committees. So to get the full picture, spending by official DFL party groups (the DFL House Caucus, the DFL State Central Committee) needs to be taken into account:

A couple more caveats: Independent expenditure groups aren’t allowed to coordinate with candidate campaigns to make these campaign expenditures, but they’re generally powered by political insiders who know a thing or two about the candidates they’d like to see win. Handwritten reports (yes, it’s 2018 and some groups still file by hand) may not have all been entered in the data yet, per the CFB. Spending on candidates who lost primaries is not included.

Campaigning in a targeted district

There’s a reason so much spending is happening in the suburbs, said Maureen Shaver, a consultant and former advisor to Gov. Tim Pawlenty.

Twelve suburban House seats held by Republicans — from Woodbury out to western suburbs like Excelsior —  went for Hillary Clinton in the 2016 election, creating a map where Democrats, seeking to gain control, are trying to play offense, while Republicans play defense, Shaver said. Other seats that went DFL in 2016, such as the Apple Valley seat currently held by Erin Maye Quade, who is not running for it this November, could be pickups for Republicans.

“If you look at where there is opportunity, suburban women are voters who haven’t necessarily made up their minds. They’re not as partisan, and they vote,” she said.

The House district seeing the most outside spending so far is 37A, according to CFB filings. There, Erin Koegel, DFL-Spring Lake Park, is defending the northern suburban seat she won by less than 3 percentage points in 2016 in a rematch against Republican Anthony Wilder.

The Coalition of Minnesota Businesses has spent more than $75,000 against Koegel and for Wilder, mostly on a cable ad buy. The Housing First Fund, the Minnesota Jobs Coalition and Pro Jobs Majority have spent $15,000, $4,000 and $1,000, respectively, on communications in favor of Wilder.

It’s not just the northern suburbs that are seeing big outside expenditures.

That longtime Republican Rep. Matt Dean isn’t running again this year for White Bear Lake-area District 38B leaves an open seat. This year, Republican Patti Anderson and DFLer Ami Wazlawik, who lost to Dean by 14 percentage points in a 2016 bid for the seat, are running.

More than $86,000 has been spent on mailers and cable buys attacking Wazlawik by the Minnesota Jobs Coalition and the Coalition of Minnesota Businesses, per CFB records. The Coalition of Minnesota Businesses and the Pro Jobs Majority have spent $2,700 in favor of Anderson.

Wazlawik says she knows of four or five outside money-funded mailers attacking her that have arrived at district homes.

For her part, the candidate thinks all the outside money is bringing negativity to the race.

“I think people don’t like it and they want to be able to make their decisions based on conversations they have with people and what people want to do,” Wazlawik said.

While suburban districts — combined — have drawn the lion’s share of campaign cash, the single race seeing the most independent expenditures flowing from DFL state party arms is 14B, a St. Cloud district that’s in the minority of non-suburban races being targeted.

This St. Cloud-area district has seen nearly $38,000 spent so far to help Democrat Dan Wolgamott, but that could end abruptly. Wolgamott’s opponent, Republican incumbent Jim Knoblach, dropped out of the race last month following allegations that he sexually abused his daughter, reported by Minnesota Public Radio. Non-party groups had spent about $9,400 to help Knoblach.

The Senate special

The Minnesota Senate isn’t up for re-election until 2020, but there is one Senate race on the ballot. There’s a special election in SD13 to fill the vacancy created when Sen. Michelle Fischbach resigned to become lieutenant governor.

Republican Jeff Howe and DFLer Joe Perske are vying for that seat, which Fischbach held by a very comfortable margin of 37 percentage points in 2016.

The GOP’s Senate Victory Fund has spent $61,800 to influence this race. Also spending in that race: the Advance Minnesota Independent Expenditure Committee ($1,500 pro-Howe), Pro Jobs Majority ($49,000 to help Howe) and the DFL State Central Committee ($126,000 pro-Perske).

Groups making independent expenditures toward November are just getting started, Shaver said, speculating voters in competitive districts could see as many as 40 or 50 mailers before Election Day.