AUGUSTA – A large field of candidates, some wealthy Republican hopefuls and public money have combined to make this the most expensive gubernatorial primary campaign in state history, state officials and political activists say.

Estimates prepared by the state ethics commission show that the seven Republicans and four Democrats in the race have raised nearly $5.2 million to date.

That’s almost as much as was spent on the entire 1994 gubernatorial campaign, which also drew a large field, said Paul Lavin, assistant director of the Maine Commission on Governmental Ethics and Election Practices.

In 1994, when eight Republicans and five Democrats ran in the primaries, the campaigns spent a total of $5.4 million through the November vote, he said.

Nearly six weeks before this year’s June 8 primaries, it won’t take much to surpass that total during the primary season alone.

“It’s certainly the most expensive primary,” said Dan Billings, a lawyer in Waterville who is backing Republican Steve Abbott.

Billings, a freelance political columnist for the Kennebec Journal and Morning Sentinel, said that, unlike in 1994, there are candidates in this field who are able to donate large sums of their own money to their campaigns.

Republican Les Otten has already contributed $1.2 million to his campaign, which reported receipts of nearly $1.4 million.

Bruce Poliquin, also a Republican, has chipped in more than $550,000 of his own money and now has a total of $860,000, according to reports filed with the state this week.

“You have some wealthy individuals who, as is their right, are spending some of their own fortunes,” Billings said.

Republican Bill Beardsley reported raising $300,000 — $250,000 of it from his own pocket, according to the reports. And Waterville Mayor Paul LePage gave his campaign a $110,000 loan in its $217,000 total.

Republican Sen. Peter Mills has $600,000 in public campaign money under the Clean Election Act; Abbott has raised almost $300,000; and Matt Jacobson has $150,000.

Among the Democrats, Steve Rowe has raised $424,000 and Rosa Scarcelli reported nearly $324,000.

Democrats Patrick McGowan and Senate President Elizabeth Mitchell, running as clean election candidates, have initial disbursements of $400,000 each, which could grow to $600,000 if Rowe and Scarcelli raise more.

This week, Democrat John Richardson pulled out of the race after the ethics commission found that some of his campaign workers had violated clean election standards while collecting checks needed to qualify for the funding.

Kay Rand, who worked on the 1994 campaign of the eventual winner, Angus King, an independent, said the campaign spent money during the primary season even though King didn’t have to compete in one.

She said several things have changed since then, including the advent of the taxpayer-funded clean election system, which guarantees candidates who qualify a maximum of $600,000 for the primary and an additional $1.2 million for the general election. (Rand also writes a freelance political column for the central Maine newspapers.)

“Clean elections has upped the ante and increased the spending,” she said. “Even candidates who are going to poll marginally on Election Day are going to be able to spend a significant amount of money.”

In addition, it costs more to advertise on television. Campaigns also need to pay attention to the Internet and pay staffers to monitor even free social media sites, she said.

“If you’re not on TV, you’re not running an effective campaign,” said Rand, who is supporting independent Eliot Cutler this year, including giving a $250 donation, but is not working formally for his campaign.

Billings said that while it’s interesting to note how much each campaign has raised, winners can’t be picked based on the money spent.

“You have to spend a certain amount of money to be in the game,” he said. “But it’s not like the person who spends the most money automatically wins.”