MOSCOW — President Vladimir Putin thanked Russians Friday for his landslide re-election to another six-year term, pledging to lead the country to an economic “breakthrough.”

Putin’s live televised statement came shortly after the Central Election Commission officially declared him the winner of Sunday’s election with nearly 77 percent of the vote, putting him on track to become the nation’s longest-serving leader since Josef Stalin.

“Such a powerful civic activity, your responsibility and consolidation are extremely important now when we face serious domestic and external challenges,” Putin said.

The massive victory — Putin’s best-ever electoral showing — will strengthen the president’s hand as he ponders his choices for shaping Russia’s political future beyond 2024: groom a dependable successor, scrap term limits or create a new position of power to keep ruling the country after his fourth term ends.

Putin vowed to fulfill his campaign promises, but warned Russians that “it would be utterly irresponsible to promise to do it instantly.”

He said that the country needs to make a “real breakthrough” in many spheres and move to encourage economic growth, raise living standards, modernize health care and education, revive the infrastructure and solve environmental and other problems. He stressed that Russia needs to make a “technological leap” to meet those challenges.

Putin also emphasized the need for alliances to achieve the ambitious goals, saying that “political affiliations mustn’t divide us.”

“Our unity, responsibility, a common vision of our goals and aspirations by millions of people must drive Russia forward,” he said. “I’m sure that together we will succeed.”

Putin has never faced a serious threat to his rule since he came to power on the eve of the new millennium. He won 53 percent of the vote in the 2000 presidential election, 71 percent in 2004 and 63 percent in 2012.

The Sunday election came amid accusations that Moscow was behind the nerve-agent poisoning this month of a former Russian double agent in Britain, and that its internet trolls had waged an extensive campaign to undermine the 2016 U.S. presidential election.

The Western accusations ultimately bolstered Putin among a populace that sees him as their defender against a hostile West and a symbol of Russia’s resurgent power on the world stage.

Communist Pavel Grudinin came in a distant second with 11.8 percent. Third was ultranationalist Vladimir Zhirinovsky with 5.6 percent. The only candidate to openly criticize Putin during the campaign, liberal TV star Ksenia Sobchak, won just 1.7 percent.

Putin’s most serious rival, opposition leader Alexei Navalny, was barred from the race because of a criminal conviction widely seen as politically motivated.

Observers reported numerous incidents of ballot stuffing and unprecedented pressure on Russians to vote to raise the turnout that topped 67 percent. The Organization for Security and Cooperation in Europe said that the Russian state media’s extensive coverage of Putin’s activities gave him a significant advantage in the race.

Ella Pamfilova, chairwoman of the Election Commission, said at the commission’s session on Friday that the vote was free and fair. She insisted that ballot stuffing incidents and other violations were rare and quickly dealt with.

“We have created an unprecedented full-proof system … ensuring protection from fools, provocateurs and criminals,” she said.