The debate is over the definition of marriage, and it won't be cheap.
New campaign finance reports show millions of dollars will be spent on deciding a constitutional amendment that would define marriage as between a man and a woman.
Reports released Tuesday showed a snapshot of how much money will be spent on the November ballot measure, with gay marriage supporters outraising opponents.
The group opposing the constitutional amendment, Minnesotans United, has been ranking in the big bucks.
Campaign finance reports, due by midnight Tuesday, show Minnesotans United has raised more than $3.1 million so far in 2012 – 90 percent of which came from contributors within the state.
Among them, former Supreme Court Justice Kathleen Blatz, chipping in $2,000.
The Pohland brothers raised $300,000, and $69,000 was raised from Gov. Mark Dayton's family.
The money will go toward a sophisticated ground game, with hundreds of volunteers and eight headquarters throughout the state.
But this will most likely be an air war.
"We know the other side comes in late in the game and run some of the most disheartening ads you can imagine," said Richard Carlbom, campaign manager for Minnesotans United.
The other side is Minnesota for Marriage, and they're not quite so easy to get a hold of.
Fox 9 stopped by their office Tuesday, which is actually a post office box at a Roseville UPS store.
When finally reached by phone, a spokesperson declined an interview, sticking with a press release saying they've raised $1.4 million.
In a statement they said: "Our opponents are raising money from same sex marriage activists across the country...
We don't have to match our opponents spending; we only need to mobilize people who believe marriage should be protected."
Minnesota for Marriage wouldn't provide their actual finance report or a list of individual donors.
And so, voters are left with a P.O. box and a press release on one side, and a high-roller party on the other.
"This will not be easy and on election day it'll be a razor thin margin and we want to be on the winning side of that," said Carlbom.
To underscore that point, the latest poll numbers show a real flux in voters' opinions.
Forty-nine percent now oppose the amendment that would define marriage in Minnesota as between a man and a woman and 43 percent support it – a flip from four months ago when the majority supported the amendment.