For Putin, an election win will be easy. The next six years, a lot harder.

After Sunday's election, Vladimir Putin will have to address geopolitical crises and economic reforms he has been putting off – and find his successor – before he likely leaves the Kremlin for good in six years.

After nearly two turbulent decades in power, Vladimir Putin on Sunday will be overwhelmingly handed another six-year term by Russian voters, one that may prove his most challenging yet and which – under Russia's current constitution – should be his last.

Few Russian leaders have lasted as long or more radically changed the face of this gargantuan and unwieldy country than Mr. Putin. He has defied regular predictions of his political demise, and re-invented himself more than once. As he steps into what will be effectively his fifth term in office, he will need to do so again.

Today's Russia, with all of its strengths and flaws, is very much the product of Putin's priorities. It has proven far more resilient than critics at home and abroad ever expected, while forecasts of doom have become a greatly devalued currency. It will now fall to Putin himself to confront the serious problems that his own choices have instigated.

These include deep alienation from the West, which grows worse by the day, with the accompanying deprivation of Western finance and technology that Russian business had earlier relied on; economic stagnation that has so far resisted all Putin's pledges of reform; and a top-heavy and corrupt bureaucracy. And, perhaps most crucial of all, Putin must create a plan to prepare Russia for life without him.

“Putin has been successful in consolidating political power, and keeping Russians united behind him,” says Nikolai Petrov, an expert at Moscow's Higher School of Economics. “But it has been at the expense of putting off a lot of needed changes in the Russian economy and the political and legal systems. The time has come to pay the price.”

Putin's popularity

The election that will ordain Putin is a relatively new innovation in the history of Russia, where dynasties, revolutions and politburos traditionally ensconced the leader. Still, there is no suspense about the outcome because it is not an exercise in free and fair political competition.

But neither is it meaningless. A bevy of competitors, representing real opposition viewpoints, have had the opportunity to express themselves more-or-less freely during the campaign, although Putin never deigned to debate them directly. Still, the process has been rigorously stage-managed by the Kremlin, with state media creating a sense of inevitability around him, and potentially disruptive rivals like Alexei Navalny excluded from the ballot in advance.

The main factor that ensures Putin's easy re-election, however, is his undeniable popularity among Russians.

It may be little appreciated in the West, and only reluctantly conceded by Putin's domestic opponents, but the former KGB colonel inherited a country on the verge of collapse 18 years ago. He reunited it under strong central power, oversaw a decade of strong economic growth that spread a semblance of prosperity throughout much of the society, weaned Russia from dependence on Western financial institutions and advice, rebuilt the military, and gave Russians a sense of being citizens of a great power once more.

“Putin has proven himself to be the right person for Russia, over and over again,” says Sergei Markov, director of the independent Institute of Political Studies and a former Kremlin adviser. “Of course he made a lot of mistakes, and he has a lot of problems facing his next term. But people in the West don't understand how Russians view him. He isn't comparable to his contemporaries, like Angela Merkel, Emmanuel Macron, or Donald Trump. We can already see that he is a giant of Russian history, something like our FDR or Charles de Gaulle.”

The last pre-election poll, carried out by the state-funded VTsIOM public opinion agency last week, found that 74 percent of Russians intend to vote on Sunday, and of them 69 percent say they will cast their ballots for Putin. Coming in a distant second is Communist candidate Pavel Grudinin with 7 percent, ultra-nationalist Vladimir Zhirinovsky with 5 percent, liberal Ksenia Sobchak with 2 percent, and five others running at 1 percent or less.

Russia's geopolitical woes

The most acute feature of Putin's current six-year term was the disastrous collapse of relations with the United States and the West in general. The worst phase began, ironically, amid Putin's biggest attempt to win Western acceptance and respect by staging the ultra-expensive 2014 Winter Olympic Games in Sochi. The overthrow of Moscow-friendly Ukrainian President Viktor Yanukovych in a Kiev uprising prompted Putin to order the annexation of Russian-populated Crimea, and to sponsor a still-ongoing pro-Russian rebellion in eastern Ukraine.

That led to escalating Western sanctions against Moscow, and a seemingly endless train of diplomatic crises, including sanctions and embassy expulsions over Russia's alleged interference in US elections, Olympic doping scandals, and the current intensifying spat around the nerve gas poisoning of a former Russian double agent in Britain. On Thursday, the US levied new sanctions against several Russian individuals and entities in connection with election meddling.

Through all this the Russian public has stood by Putin; indeed, his approval ratings have remained over 80 percent. Russians seem to appreciate his defiance of Western pressure, and there is no sign of them abandoning him.

Yet, there is no doubt that Russia is boxed-in by his choices. Confrontation with the West was the downfall of the former USSR, and many Russian experts fret that that ongoing sanctions may gradually bury Russia's hopes of modernizing its economy by absorbing cutting-edge Western technologies and integrating with world markets. The Kremlin has made much of plans for a “pivot to Asia” as an alternative to Western engagement, and that may yet change the face of global geopolitics, but it remains a largely hypothetical work-in-progress.

“Relations with the West took a turn that Putin didn't expect, and he has probably underestimated its long-term consequences,” says Mr. Petrov. “He didn't anticipate the outcry over the annexation of Crimea. He may have hoped that the election of Donald Trump would set things right, but that definitely didn't happen. Putin is a person who likes to keep all his options open, but these changes look irreversible. That is going to haunt his next term.”

Potential flashpoints at home

Some experts say Putin sidelined economic reform after 2014 in order to deal with the international crisis. He has succeeded in fending off the double-whammy of Western sanctions and falling oil prices, and the Russian economy actually bounced back from recession, growing about 2 percent last year.

“The problem is that the growth we are experiencing is the result of state intervention, not organic private sector growth,” says Andrei Kolesnikov, an expert with the Moscow Carnegie Center. “The state is everywhere in the economy. That limits the prospects for future growth and reinforces authoritarianism in the political sphere. State capitalism cannot exist without political control. Economic monopoly requires political monopoly.

“Putin's approach in his next term will be to create a more technocratic elite; appoint people who are younger, more efficient in his eyes. He will try to do it without fundamentally reforming the system, and that means the economic stagnation will continue,” he predicts.

The last six years have seen relatively few upsurges of social discontent, though there have been some warning signals. But Kremlin plans to implement pension and tax reforms, to increase state revenue, suggest that could change.

“After the election we will be heading into a period of intense social reforms, and the likelihood of popular push-back will increase,” says Petrov. “Police forces around the country are being re-trained and re-equipped, so it seems that authorities are expecting this.”

Post-Putin Russia

But the biggest uncertainty revolves around Putin's plans for handling succession, a critical question that he has so far failed to address. Both on the grounds of his advancing age – he will be 72 in 2024 – and the Russian Constitution's limitation of a president to two consecutive terms, some hard decisions will have to be made.

“Putin is going to be a lame duck for the next six years and that means that elites will be scheming and struggling [over the succession] for all that time,” says Olga Kryshtanovskaya, Russia's leading expert on the country's shifting elites.

“It takes a generational form, with older groups wanting Putin to stay in some way, because everything they have depends on him. Younger people want reforms, a change of the guard, upward mobility for themselves. Putin is still able to be the arbiter of this, but as the question of succession becomes more acute, the struggle will intensify,” Ms. Kryshtanovskaya says.

“This has happened many times before in Russian history,” she adds. “The long reign of a czar ends, and is followed by turmoil, a war of all against all. We need to avoid this nightmare, and I hope that Putin understands that.”