This time next year, the Republican candidate for governor of Connecticut will be looking for voting support far beyond his or her meager base of just over 410,000 registered party members. He or she will be contending with Gov. Dannel P. Malloy for his base of 720,000 Democrats and both candidates will be most concerned, and rightly so, with the largest bloc of 817,000 unaffiliated voters unwilling to ally themselves with either party. There are more unaffiliated voters than Democrats or Republicans in an astounding 140 of Connecticut's 169 towns. Democrats have the lead in 22 towns and Republicans, in just seven.

The Republican candidate will be trying to be elected after having been nominated in a party primary that attracted just 120,000 registered Republicans, if the turnout is similar to what it was in 2010. The Democrats, considering their numerical advantage, did even worse, with only 180,000 of their 700,000 registered voters choosing Mr. Malloy over Ned Lamont.

The problem both parties have is their policy of beginning each election campaign by keeping potential supporters away with their closed primaries. To add to the problem, these primaries are dominated by true believers who tend to be to the right or left of most Connecticut voters.

As the nation has become more polarized, it is growing increasingly difficult for a candidate to move from the extreme views of his or her party to the more centrist views of a healthy portion of the electorate. This becomes both a tortuous journey for the candidates and the voters.

It reached new heights - or lows - during the 2012 Republican presidential primaries when extremist candidates like Michelle Bachmann, Herman Cain, Rick Santorum and Rick Perry, who had no chance for the nomination, dominated the primary debates and became the faces of the Republican Party. This required the eventual nominee, Mitt Romney, to compete first for the party's extremist vote and left an ideologically wounded Mr. Romney to have to explain himself in the general election.

And now, there are signs of this infection spreading to Connecticut. During the recent crisis over the attempt by the Tea Party Republicans controlling the House to shut down the government if they couldn't change Obamacare, none of the Republicans running for governor could bring themselves to renounce the extremists.

Tom Foley, the 2010 Republican nominee, even said, "I support what they're doing." Danbury Mayor Mark Boughton, who, like Mr. Foley, is "exploring" a run at this point, acknowledged both parties had some answering to do, but he characterized linking changes in the health care act to shutting down the government as business as usual. State Sen. Toni Boucher criticized Obamacare and said past shutdowns hadn't been so bad.

State Sen. John McKinney insisted both parties were to blame, but in an interview with The Day's David Collins, he also refused to criticize the tactic of linking a government shutdown to changing the health care law.

"This is classic pre-primary politics; reach to the extremes of your party, then hustle back to the center before the general election," Mr. Collins wrote.

So what's a party to do if it wants to nominate candidates who can win the favor of voters who occupy the constantly expanding middle ground?

That's easy. Open its primaries to unaffiliated voters. And if one party does it, the other will surely follow.

Until the 1980s, Connecticut law barred unaffiliated voters from participating in party primaries, and in 1984, when the Republican Party tried to open its primary to independents, it was overruled by the Democratic legislature. The party went to court and in 1985 , a three-judge federal appeals court ruled the parties, not the states, should decide whether to open up their primaries.

So thanks to forward looking Connecticut Republicans 30 years ago, parties in many states can and do take it upon themselves to open their primaries. Connecticut Republicans started it and, as we have pointed out in the past, Republicans, as the perennial minority party, would have the most to gain by being first to open their primaries here.