political parties in Massachusetts are approaching a crossroads, as fewer new registrants choose to affiliate with either party and the number of unenrolled voters climbs to historic highs. Since 1978, the number of unenrolled voters in Massachusetts has soared by 97 percent, while the two major parties each added just 9 percent to their rolls. Since 1990, unenrolled voters have outnumbered Democrats and Republicans, and since 2008, have been an outright majority of voters in the Commonwealth.

The number of voters in the Massachusetts Republican Party has been a cocktail party punch line for some time. But the Democratic Party is also declining as a share of the overall electorate.

While a candidate’s party affiliation will remain an important signal for voters, funders, and campaign operatives, there is nothing on the horizon which suggests party registration trends will change anytime soon. Younger voters are the least likely to choose a party when registering. As today’s younger voters become a larger share of tomorrow’s electorate, the percent of unenrolled voters is likely to keep climbing, unless something happens to interrupt the trend toward registering without a party.

Part of what is driving the rapid growth of unenrolled voter counts is the apparent lack of interest in registering with a party among younger voters. Younger Massachusetts voters are far less likely to choose a party affiliation than older voters, with 60 percent of those under 22 choosing to register unenrolled. This is 10 points higher than those in the middle of the age spectrum, and 20 points higher than the oldest of the Commonwealth’s voters.

Behind this trend toward registering unenrolled is elevated skepticism among younger voters about the benefits offered by either party, and the magnitude of differences between the two. National polling shows younger people are less trusting in a variety of institutions, and political parties are no exception. Young people are the least likely to see major differences between the two major parties, with just 31 percent of millennials saying there is a “great deal” of difference between the two parties, the lowest of any age group. This ambivalence is a key reason why young voters are more and more likely to eschew registering with a party in favor of remaining unenrolled. They are also less likely to self-identify as either Republican or Democrat when asked how they lean by pollsters.

Democrats can take comfort in knowing that, for now, younger people skew heavily toward the Democratic Party, both in their values and their vote choices. In 2012, Elizabeth Warren enjoyed a roughly 20-point margin among voters under the age of 29, according to exit polls. But this preference for Democrats could change, given young people’s skepticism about both parties, and their apparent lack of long-term commitment to the Democratic Party. If Republicans can offer political ideas more reflective of young people’s values and ideals, there is nothing to suggest party loyalty alone will keep them pulling the lever for Democrats.

With more voters abandoning party registration, parties face a long-term reckoning in maintaining their value. In some states, registering with a party enables a voter to participate in party primaries. But, in Massachusetts, unenrolled voters can participate in either primary without affecting their registration status.

This pressure on parties is exacerbated by the diminished role of parties in fundraising, as more dollars flow to super PACs and other outside groups that recent court decisions have allowed to flourish as long as they operate independently of individual campaigns.

Despite these growing challenges, parties still enjoy a number of advantages in terms of the role they play in forming campaign infrastructure and providing important cues to voters.

First off, parties still provide valuable campaign and fundraising advantages. Independent candidates have a much harder time attracting campaign operatives, whose career success often depends on remaining in good standing with their chosen party. And, without the credibility that party affiliation provides, independent candidates have a harder time attracting money from donors who want to curry favor with potential winners.

Parties also provide access to the considerable technological and data infrastructure they have developed in recent years. Building competitive data and technology infrastructure from scratch and on a campaign timeline is not feasible, given the enormous strides the parties have made over the last 10 years.

Finally, decades of political science research have shown party affiliation is an important — often the most important — characteristic many voters will consider when deciding how to cast their ballot. Even while more register independent, many of these same voters think of themselves as closer to one party or the other. While 52 percent of voters statewide are registered as unenrolled, only about 17 percent of voters say they don’t lean either Democrat or Republican when asked in polls. In other words, there are far fewer actual independents than examining the voter rolls would suggest. Thus, even a weakened party infrastructure with fewer registered members can provide a candidate an essential partisan label which will draw votes.

Because of these advantages provided by party affiliation and infrastructure, the changes in party registration figures in Massachusetts do not suggest that independent candidates have any better chance now than they did in past years. This year, despite a choice of several qualified and well-funded independent candidates in the race for Governor, none of them poll in double digits as of deadline. This could change, of course, but changing registration figures alone are not sufficient evidence that voting dynamics will be different this year.

The disconnect between more unenrolled voters and tepid support for independent candidates is evident in past elections. Unenrolled voters have been in the majority for years but, two independent candidates have broken 5 percent in recent years: Tim Cahill in 2010 and Christy Mihos in 2006. Even with respectable spending by both campaigns, neither independent candidate even came in second in a single town in Massachusetts.

The state’s miserable record of supporting independent candidates highlights the challenge ahead for Evan Falchuck, Jeff McCormick, or Scott Lively. The most recent examples of lifelong independents winning statewide office come from Maine and Vermont. In each of those cases, the winning candidates were clearly aligned with the preferences of one party, even if the candidates themselves were not affiliated with the party on paper.

In both cases, Democrats were far more likely to support the independent candidate than were Republicans. Republicans in Maine voted against now-Sen. Angus King by a 45-point margin in 2012, similar to the 49-point margin against Vermont Sen. Bernie Sanders in the same year. The winning formula in both cases was not to appeal equally to both parties, as a theoretical “centrist” might. Instead, each drew support from a specific part of the ideological spectrum, and in each case, won votes from the party with the most self-identified members in the state on Election Day.

Steve Koczela is the president of the MassINC Polling Group, a subsidiary of MassINC, which publishes CommonWealth.