AUGUSTA – With seven Republicans running, the nominee could win with less than 10 percent of the votes of registered party members.

To Secretary of State Matthew Dunlap, that should send a strong message to voters that June 8 is a very important Election Day.

“This election will be decided by a few hundred votes,” he said. “The world is run by people who show up.”

It may seem hard to believe that, with 259,502 Republicans registered in Maine, the party’s nominee for the general election could win with fewer than 20,000 votes.

But Dunlap said primaries have historically low turnout — about 15 percent to 20 percent. This year, 70,000 to 90,000 Republicans are expected to cast ballots in the GOP primary, Dunlap and others said.

Democrats — with four candidates running — expect about 100,000 voters in their primary, although Dunlap said that seems high. There are 317,977 registered Democrats in Maine, according to the state.

“A small coalition of voters — 35,000 to 40,000 — could surely be enough for one of the Democrats to be victorious on primary day,” said Jesse Connolly, a political consultant and former chief of staff for House Speaker Hannah Pingree, D-North Haven.

Connolly, who is not actively working on any campaign and describes himself as undecided, said candidates are running aggressive field operations to identify supporters who will turn out on Election Day.

“There’s a lot of technology and looking at past voter history to understand who the likely voters are,” he said.

Patrick Murphy, president of the polling firm Pan Atlantic SMS Group in Portland, said predicting turnout — or a winner — is purely “guesswork” at this point.

“I think we’ve got a very spirited race on the Republican side,” he said. “I’m not sure it’s as spirited on the Democratic side.”

Among the Democrats — Steve Rowe, Rosa Scarcelli, Patrick McGowan and Senate President Elizabeth Mitchell — Murphy said he thinks all “will do pretty well.”

On the other side, there are “four to five” — he didn’t want to single them out — of the seven he would classify as “having a very strong shot.”

The Republican field includes Bruce Poliquin, Les Otten, Sen. Peter Mills, Waterville Mayor Paul LePage, Matt Jacobson, Bill Beardsley and Steve Abbott.

David Emery, a consultant to Otten who is a pollster and former congressman, said turnout will be very hard to predict. He expects 70,000 to 78,000 Republicans to vote, reflecting the 2006 and 2002 turnouts.

But the wild card will be Question 1, a people’s vote on repealing a tax reform package.

Emery said he’s not sure whether the question will attract more people to the polls. Others say the bond questions may also bring out certain groups that might not normally participate in a primary.

“This one, I think, is one of the most difficult primaries in history in terms of making predictions,” Emery said.

And, with seven candidates, it could take just one stumble — or one strong day — to change the mix.

“All it takes is a really good day or a very bad day,” he said.

Felicia Knight, spokeswoman for Abbott, said primary campaigns are different from fall elections for a number of reasons.

Even though each candidate is working to get a much smaller segment of the electorate, he or she must still advertise on television, organize volunteers and go door-to-door to win.

“Based on the fact that most people in the primary share a certain set of values, to move beyond that you need to show the candidate’s strength of ideas, vision and problem solving and leadership,” she said.

Emery, who finished third in a three-way GOP gubernatorial primary in 2006, called it “a fascinating campaign.”

He, too, urged people to vote, noting that even independents can vote in a primary if they enroll in a party on Election Day.

“To me, the thing that is frustrating is you run into people who say there are too many people running, they aren’t going to vote in the primary,” he said.

Maine Today Media State House Reporter Susan Cover can be contacted at 620-7015 or at:

scover@mainetoday.com