Minnesota Democrats benefited from a flood of campaign spending that swamped their Republican rivals during the 2018 election.

Facing the prospect of full Republican control of state government for the first time in half a century, major Democratic donors — including a handful of wealthy individuals and public-sector unions — unleashed a torrent of cash to help keep the governor's office in DFL hands. These prodigious donors also targeted key Minnesota House races that handed the gavel to new Speaker of the House Melissa Hortman, D-Brooklyn Park.

Political groups spent $11.8 million in independent expenditures to support Walz or oppose Republican candidate Jeff Johnson through advertising and voter outreach. Johnson got $2.6 million from such groups, according to reports released Friday by the state Campaign Finance and Public Disclosure Board.

"It shows the hypocrisy of the Democrats," said Kevin Poindexter, executive director of the Republican Party of Minnesota. "Big money in politics is bad, unless it works in their favor."

State DFL Party Chairman Ken Martin said he would like to reverse the trend of expensive campaigns and money flowing into politics, but the reality is fundraising is necessary to win. A record amount of money was spent in support of his party, Martin said, describing that as a sign of energy and enthusiasm.

"We're proud of that, but at the same time it highlights how much money is coming into politics," Martin said.

Fundraising totals released Friday show the full picture of 2018 political spending in the state, including the final push before Election Day.

Walz's campaign received about $1.6 million more than Johnson's. Walz's end-of-year report shows his campaign raised nearly $4.2 million, including a public subsidy of about $480,000. Campaigns face far more restrictive rules about raising money than outside groups, which can raise and spend unlimited sums.

Johnson, who lost by more than 11 percentage points, faced a greater disadvantage once spending from outside groups was factored in. Those groups spent $33 million in Minnesota races last year, according to data from the campaign board.

The top three largest spenders were all aligned with Democratic candidates. In total, the Alliance for a Better Minnesota, Minnesota DFL State Central Committee and Minnesota Victory PAC spent nearly $17.4 million to elect Democrats like Walz.

Charlie Weaver, executive director of the Minnesota Business Partnership, said no amount of money could have saved many Republican candidates, given the fervent opposition to President Donald Trump that energized suburban voters.

Still, "money's a factor," said Weaver, whose group represents the state's largest companies like Target and Cargill.

Labor unions contributed millions to various political parties, committees and funds, largely in support of Democratic candidates. The teachers union Education Minnesota spent and disbursed more than $5 million and the American Federation of State County and Municipal Employees contributed nearly $2 million to various groups, including the House DFL Caucus.

Outside groups channeled money into state House races, with an intense focus on the suburbs. Democrats swept into control in the House last year, gaining 18 seats previously held by Republicans.

The House DFL Caucus raised more than $5 million in 2018, a 26 percent increase over its 2016 fundraising. The House Republican Campaign Committee raised roughly half as much as its Democratic counterpart and saw a slight uptick in the amount raised compared to the 2016 election year.

The three House races that generated the most outside spending were the battles for seats now held by Rep. Ginny Klevorn, D-Plymouth; Rep. Alice Mann, D-Lakeville; and Rep. Kristin Bahner, D-Maple Grove. Outside groups spent more than $500,000 on each of those races, where three Republican incumbents were ousted.

Republican candidate for attorney general Doug Wardlow also faced a significant cash disadvantage. Democratic donors to outside groups devoted far more on independent expenditures to benefit newly elected Attorney General Keith Ellison — about $1.9 million, 12 times as much money as was spent on behalf of Wardlow.

Only one state Senate seat was on the ballot. But with the chamber evenly split between Republicans and Democrats, the St. Cloud-area special election to determine Senate control was costly. Democratic groups put in $1.6 million to help Joe Perske, more than twice what was spent on the winner, Republican Jeff Howe.

Major individual donors in 2018 included Alida Rockefeller Messinger, a longtime Democratic contributor and former wife of Mark Dayton. She gave about $1.9 million to various funds, committees and candidates in 2018. Joan and Robert Cummins, who have a history of giving to conservative causes, spent more than $1.7 million on Republican-affiliated committees and candidates.

Staff writer Torey Van Oot contributed to this report.

Jessie Van Berkel • 651-925-5044