Frida Ghitis, a former CNN producer and correspondent, is a world affairs columnist. She is a frequent opinion contributor to CNN and The Washington Post and a columnist for World Politics Review. The opinions expressed in this commentary are her own.

(CNN) When a politician with authoritarian tendencies takes office -- even in a democratic country -- there's no way to know what the future holds. It's easy to take comfort in the prospects for setting everything right in the next election, to feel reassured by massive turnout in protests against excesses, and to believe that democracy is being protected by court rulings, by Congress, and by human decency.

But recent history in the many countries now governed by authoritarian populists has shown that there's more reason for alarm than for comfort, more reason to remain on guard than to relax.

The struggle to defend democratic norms is not only raging in the United States over the treatment of migrant families and over the President's pernicious pattern of lying and attacking the press . It is being fought in a number of nations whose leaders have shown disdain for democratic traditions, with occasionally unexpected results.

Much to just about everyone's surprise , the strongman in Turkey, President Recep Tayyip Erdogan, faces a tough election this Sunday. Erdogan, a NATO ally, has steadily built up his power while destroying democratic protections. The playing field is completely tilted against the opposition. Erdogan's political opponents have been jailed , along with scores of journalists . He has decimated independent media and has deeply polarized the country.

Erdogan may have expected to win in a landslide, but what looked like certain victory was called into question with the Turkish economy's crippling inflation and the opposition finding a firebrand candidate

Ahead of the vote, Erdogan has launched a "wag-the-dog" military campaign that looks like an effort to bolster his patriotic support. Many believe Erdogan's rule is in peril. We shall see. The last time Erdogan faced a close vote, on a referendum over increasing the President's power, he ended up winning under circumstances that many deemed unfai r -- a charge that Turkey's Foreign Ministry rejected.

The new fashion in authoritarianism requires preserving a veneer of democracy. That leaves a chink in the armor of strongmen that can create an opening for defenders of liberal democracy, a system that protects individual rights and is based on rule of law, equality -- including for minorities -- a free press, free expression and fair elections, among other things.

The best way to defend against a slide to authoritarianism is by voting against autocratic demagogues. But the power of the ballot grows weaker with every passing day after they take office. That's because autocrats excel at gradualism, increasing their hold on power bit by bit, until democracy becomes a mirage. The process is all the more insidious because demagogues often operate in a cloud of misinformation and propaganda, so the people cannot see their democracy being stolen until it is gone.

Consider Russian President Vladimir Putin's control of the media, which has allowed him to use gaslighting techniques against his critics, to control the story, and keep his approval ratings sky high. All this despite an economy on the mend from its 2015 recession and the thorough dismantlement of Russia's once-promising democratic prospects, complete with the assassination of opposition politicians and critical journalists (which the Kremlin has denied responsibility for). By now and for the foreseeable future, elections offer little solace to pro-democracy Russians.

Or look at Nicaragua, where President Daniel Ortega is now in his fourth term . Ortega and his wife and would-be successor managed to take control of all elements of power and even get a convenient new constitution . But it all popped like a balloon a few weeks ago over the cutting of government pensions. When popular anger exploded, the regime responded with bullets. Now the impoverished country has become a battlefield with an uncertain future

The longer autocrats stay in power, the harder they are to remove. Early on, elections can work. But ask Venezuelans what happened to them. The regime led by President Nicolas Maduro kept up the charade, pretending to be a democracy while monopolizing power. Even so, the opposition managed to defeat the ruling socialist party in the 2015 midterm elections, with most Venezuelans desperate for change.

Much less far gone, but on the autocratic path , are Hungary and Poland, where populist nationalist governments, are stoking the anti-immigrant flames that fuel their popular support. Already in Hungary the government controls most of the media, which has facilitated the spread of pro-government propaganda and bolstered Prime Minister Viktor Orban's election campaigns, utilizing bigotry

The countries I mentioned above have thin democratic traditions.

In countries with strong democratic underpinnings, the courts still function, the opposition still speaks, the media -- despite attacks by the powerful -- can still do their job. And above all, the people have a strong and enormously influential voice.

So, here's the lesson from this dark wave sweeping the world: When a democratic country elects a politician with suspicious tendencies, defenders of democracy cannot sit back and wait for the next election. Sure, elections are the best way to achieve definitive results, when that is still possible.

But when Election Day looms far in the distance, it's important to maintain the pressure, to call out the lies, to counter the propaganda, the corruption, the violation of the country's moral ideals, and the steady erosion of democratic values that have become the calling cards of modern-day autocrats.

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