BOSTON — When Massachusetts voters cast ballots on Election Day, they not only picked winners and losers in a host of key races, they also gave a big boost to those seeking an alternative to the state’s two top political parties. By the time polls closed, the number of parties with official status in the state had doubled.

The Green-Rainbow Party and the United Independent Party now join the Democratic and Republican parties as those with official status, meaning they can hold primaries and field candidates under their party banners.

But if the recent history of new parties in Massachusetts is any guide, the real work is just beginning. Now the parties must try to turn that initial success to the more difficult task of winning elected office.

That’s particularly daunting in Massachusetts, a state dominated by Democrats where even Republicans typically face tough odds.

That challenge isn’t dampening the enthusiasm of both parties, who say they’re determined to revive what they see as a moribund political culture.

“When you have two candidates on the ballot – Republican and Democrat – who don’t reflect your values, you’ve effectively had your free speech rights taken away,” said John Andrews, outgoing co-chair of the Massachusetts Green-Rainbow Party and a member of the party’s national committee.

Evan Falchuk, who is hoping his United Independent Party takes root in Massachusetts, said he’s also responding to disillusioned voters.

“What we’re offering people is the opportunity to build a framework that is going to change the political landscape of Massachusetts so that policy reflects the needs and concerns of ordinary voters,” said Falchuk, who ran as his party’s candidate for governor. “That gets people pretty engaged.”

Both parties won official status during the past election by capturing at least 3 percent of the vote in a statewide race, according to unofficial returns.

In the governor’s race, Falchuk won just over the 3 percent, or more than 71,000 votes. The Green-Rainbow Party candidates for secretary, treasurer, and auditor also crossed the 3 percent bar.

Keeping official status could be tricky. Each party is pursuing a different path.

The Massachusetts Green-Rainbow Party is associated with the national Green Party, which is planning to run a candidate for president in the next election cycle in 2016.

Since the presidential contest will be the only statewide race in 2016, the party is hoping its national candidate wins at least 3 percent of the vote here to maintain its status. If not, it wouldn’t be the first time the party has lost its official status.

Falchuk is pursuing another route by trying to get at least 1 percent of registered voters to join the United Independent Party, a figure that would allow it to maintain official status. To get there, Falchuk is hoping to persuade about 50,000 Massachusetts voters to enroll.

Their efforts come at a time when Democrats and Republicans have been losing registered voters. More than half of Massachusetts voters currently aren’t enrolled in any party.

Falchuk said he and his supporters will be working hard to sign people up.

“You go out. You touch them. You talk to them. You engage them. You get them to enroll,” he said. “We’re nothing if not hard-working, determined and persistent.”

Falchuk said he’s also hoping to run candidates for state legislative seats under the party’s banner in 2016.

Massachusetts Democratic Party Executive Director Matt Fenlon said he doesn’t see a threat from the two parties, even though some of the policy goals of both parties could appeal to Democrats.

The Green-Rainbow Party, for example, supports universal health care, and Falchuk has called for an end to hospital mergers, saying they drive up health care costs.

Fenlon said Democrats, coming off a narrow loss in the governor’s race, are focusing on their core message.

“When Democrats in Massachusetts talk about our programs and our ideas, it works,” he said. “That’s what we’re going to do.”

The smaller parties are quick to dismiss the idea that they could act as spoilers – essentially drawing enough votes from one of the major party candidates who may be ideologically closer to them and ultimately tipping the election to the other major party candidate.

“What really spoils elections is when you don’t have someone on the ballot who reflects your values,” Andrews said.