PORT-AU-PRINCE, Haiti – Eight candidates in last month’s disputed presidential vote are demanding changes in Haiti’s electoral council and national police department. And if that doesn’t happen by next month, they are calling for a transitional government to oversee new general elections.

Among those signing late Sunday’s declaration was Jude Celestin, the second-place finisher who is due to face the government-backed candidate, Jovenel Moise, in a Dec. 27 runoff. The ultimatum throws that runoff into question.

The Group of Eight alliance, which includes seven of the top 10 vote-getters in the Oct. 25 first round, said that without “major changes … “fair, free and democratic elections” cannot be held while outgoing President Michel Martelly is in power.

The eight said a transitional government would be charged with adopting a new constitution, making various reforms and organizing “credible” general elections within 24 months. They did not specify how it might be formed.

The eight have been demanding an independent recount due to what they assert was “massive fraud” in favor of Moise. But election authorities say the vote was a success and they lack the authority to appoint an independent panel to verify results.

Moise’s well-financed Tet Kale party campaign has repeatedly denied accusations that it manipulated voting or the ballot count.

Haiti’s Provisional Electoral Council said Moise had nearly 33 percent of the vote and Celestin 25 percent.

While many Haitians hoped that the election would end years of political gridlock, the official results have instead brought a renewed surge of paralyzing street protests.

A recent poll by the independent research group Igarape Institute found deep public suspicion of the October election. A U.S. delegation of election monitors from the National Lawyers Guild and International Association of Democratic Lawyers Delegation said it “fell far short of minimum standards for fair elections.”

But observers from the Organization of American States said the preliminary results appeared to be in line with what they saw on election day.

Under Haitian electoral law, if a candidate selected for the runoff withdraws, he would be replaced by the next contender in line. The third-place finisher, former Sen. Moise Jean-Charles, belongs to the opposition alliance. The fourth-place finisher, Maryse Narcisse of the Fanmi Lavalas party founded by former President Jean-Bertrand Aristide, is not a member of the alliance.

Haiti’s amended constitution says the country’s prime minister would lead any transitional government.