By Matt Volz Associated Press

HELENA (AP) – Bozeman businessman Greg Gianforte has now spent more than $5.1 million of his own money to fuel his campaign against Montana Gov. Steve Bullock, while the Bullock-backing Democratic Governors Association poured in another $1.5 million into one of the closest governor’s races in the nation.

The candidates and political action committees turned in campaign finance reports Monday that detail their contributions and spending between Sept. 27 and Oct. 19. The reports show a governor’s race on track to be the most expensive in state history, as each side accuses the other of trying to buy the election.

The Montana campaign is one of the closest of the 12 governor’s races in the country, with a recent Mason-Dixon poll commissioned by Lee Newspapers of Montana giving Bullock just a 2-point edge, which is well within the 3.2 percent margin of error.

Gianforte, who sold his software company RightNow Technologies to Oracle for $1.8 billion, cut his campaign two $1 million checks over the last month, going above and beyond his previous pledge to match campaign contributions dollar for dollar. Individual donors contributed another $238,000 to him over the reporting period.

His campaign has funneled most of that money into buying television ad time, spending nearly $1.25 million on ad buys during the reporting period.

Asked about Gianforte’s self-funding, spokesman Aaron Flint said Gianforte is working to get his message out and to combat more than $5 million in attack ads against him. Gianforte has raised more from individual donors in Montana than any other challenger for the Montana governor’s office, Flint added.

“His opponent, meanwhile, is a career politician who is trying to buy this election with tax dollars, PAC dollars and from his dark money group friends who are working to shut down Colstrip,” Flint said, referring to a southeastern Montana coal-fired power plant.

The $311,334 that Bullock took between Sept. 27 and Oct. 19 puts the incumbent at more than $3 million raised for the election cycle. His biggest donations for the period topped $10,000 apiece from four union PACs and a lawyers’ PAC. The Democrat’s campaign also is spending heavily on television ads, at $803,232 in ad buys for the month.

“Mr. Gianforte has to resort to using his personal fortune because Montanans are rejecting someone who wants to fundamentally change what Montanans value about our state—from public lands to public education to equal pay for equal work,” Bullock campaign manager Eric Hyers said.

There have been relatively few outside groups making independent expenditures to influence the outcome of the race, but the ones who have are also spending heavily. Leading the pack is the DGA, which Bullock was chairman of from 2014 to 2015.

With the addition of the $1.5 million it spent over the last month, the DGA has now funneled $3.35 million into the race through the Good Jobs Montana PAC.

Good Jobs Montana also reported donations from the American Federation of State, County and Municipal Employees, the National Education Association and Montana Conservation Voters.

DGA spokesman Jared Leopold said the amount of money going into Montana is a reflection of how close the race is and to counter Gianforte’s personal spending.

“The DGA’s very invested in winning governor’s races around the country and certainly Montana’s a big race this cycle,” he said.

The Republican Governors Association’s Right Direction PAC, another outside group spending money in the Montana race, reported spending $92,755 for the period.

A newly formed PAC called Montanans for Truth in Public Schools is the third group that has spent money on ads on the governor’s race. Its ad features renowned paleontologist Jack Horner questioning whether Gianforte would spend taxpayer money to support schools that teach creationism and intelligent design.

That group spent about $9,500 to air that ad earlier this month.

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