Bulgarian President Rosen Plevneliev in Brazil in February, 2016. The interim government he appointed in 2014 infuriated Moscow by identifying Russia as a threat | Evaristo Sa/AFP via Getty Images Bulgaria caught between NATO and the Kremlin Socialists want to repair old ties with Moscow. The presidential election gives them a chance.

Bulgaria's impending presidential election is a tempting opportunity for Russia to try to haul a vulnerable eastern European country back into its strategic orbit.

Rumen Radev — a daredevil MiG-29 jet pilot — is the candidate who has set alarm bells ringing over Sofia's ties to Moscow. A loop-the-looping highlight at airshows, he is the pick of the opposition Socialists, who are desperate to repair damaged relations with the Kremlin in the vote on November 6.

Radev was shortlisted after Bulgaria's socialist leaders conducted an elaborately choreographed trip to Moscow in July. The fighter ace was formally nominated last month and has lost no time in insisting that the NATO member made a strategic blunder by alienating Russia in recent years.

His candidacy cuts to the heart of deep concerns in Washington and Brussels about Russia's ability to influence energy and defense policy in the eastern EU.

Without identifying any particular country, U.S. Defense Secretary Ash Carter warned Russia last week against "attempting to interfere with [Western] democratic processes." A leader of one of Bulgaria's minor left-wing parties has also dismissed former Air Force General Radev as a puppet of an arms lobby traditionally oriented toward Moscow.

The current president, Rosen Plevneliev, has sparked outrage in Moscow and among many Russophiles on the Bulgarian Left by striking a defiantly pro-Western tone.

Bulgaria was Russia's most dutiful vassal during the Soviet era, but the current president, Rosen Plevneliev, has sparked outrage in Moscow and among many Russophiles on the Bulgarian Left by striking a defiantly pro-Western tone.

The high-water mark of Russian rage came in June when Plevneliev addressed the European Parliament in Strasbourg. He described the annexation of Crimea as a "game changer" and starkly accused Moscow of using hybrid warfare "to destroy and bring down the foundations of the European Union — unity, solidarity and the rule of law."

"The Russians were angered at Plevneliev ... the Kremlin does not expect any Bulgarian president to be that open and straightforward," said Ilian Vassilev, Bulgaria's former ambassador to Moscow and now managing partner of Innovative Energy Solutions.

Radev pushed back against the Russia policy of the ruling pro-EU, pro-NATO center-right GERB party almost immediately after he was nominated. Explaining his views later to Bulgaria's Darik Radio, he said: "Bulgaria must have an independent foreign policy. Bulgaria must follow its own objective. We lost a lot by more or less declaring Russia our enemy."

Backroom Boyko

While less prominent than prime ministers, Bulgarian presidents are more than figureheads. The president commands the armed forces, appoints key judicial and security officials and, perhaps most critically in Russia's eyes, selects caretaker governments. Interim governments are not rare in Bulgaria, and the one Plevneliev appointed in 2014 infuriated Moscow by identifying Russia as a threat. The presidency also has limited veto powers.

Opinion polls suggest that support for the Socialists languishes far below that for GERB. But concerns about a shock win for Radev are growing because GERB has still not nominated a candidate. This has raised fears that Prime Minister Boyko Borisov, a former fireman and bodyguard, is mulling a backroom deal over the presidency to appease Bulgarian oligarchs tied to Russia. One of the most frequent criticisms of Borisov is that he has tried to serve too many masters. While declaring allegiance to the EU and NATO on one side, he has also been seen as close to Russia-linked oligarchs, including the head of Lukoil in Bulgaria.

Bulgaria's Socialists — the successors of the Communist Party whose former prime minister Sergei Stanishev now leads the Party of European Socialists — reacted with hostility to Plevneliev's Strasbourg speech. It hit a raw nerve at a time when Sofia appeared to be asserting an unusual degree of independence in spheres where Russia long felt it called the shots.

The military question is highly sensitive, as Sofia is currently dependent on Russia for parts and maintenance, placing it in an awkward position as an active NATO member.

Sofia last year denied overflights to Russian warplanes heading to Syria, and is likely to do so again when Moscow requests permission to fly to Serbia to participate in its "Slavic Brotherhood" military exercises later this year.

Bulgaria has also sought to replace its aging Soviet-era military hardware with Western alternatives such as F-16 fighter jets. The military question is highly sensitive, as Sofia is currently dependent on Russia for parts and maintenance, placing it in an awkward position as an active NATO member. Tatyana Doncheva, a former Socialist who now leads the left-wing Movement 21 party, accused 53-year-old Radev of being the candidate of a business circle "which is tied to the arms lobby."

Moscow has also slammed Bulgaria for buckling to EU pressure over the controversial South Stream gas pipeline under the Black Sea, a project that collapsed in 2014 primarily because of objections from Brussels.

Vassilev cautioned that the commercial interests at play in the election stretched well beyond the arms industry to a more complex web of "factions of the ruling elite" seeking energy deals and other big procurement projects.

To Russia, with love

The socialists have flatly rejected allegations that Moscow is dictating their choice of presidential candidate, but the timetabling and theatrics of Radev's appointment have triggered intense suspicion.

A few weeks after Plevneliev's speech in Strasbourg, Korneliya Ninova, the Socialist leader, and Georgi Parvanov, a former president and current leader of the leftist Alternative for Bulgarian Revival (ABV), headed to Moscow to participate in the 15th congress of President Vladimir Putin's United Russia Party.

Ninova used the visit to confirm that her party supported the lifting of EU sanctions against Moscow, imposed over the conflict in Ukraine.

Days after her return from Moscow, Ninova announced that Radev was one of six potential Socialist candidates selected by party members.

Metodi Andreev, a parliamentarian from GERB, considered it likely that Russia had told Ninova and Parvanov to nominate him, an accusation strenuously denied by ABV politicians. Meanwhile Maya Manolova, the country's ombudsman and former Socialist MP, protested that Radev's selection was fixed.

One of Moscow's main grievances with Plevneliev was the caretaker government he appointed in 2014. Russia and the Bulgarian Socialists were astounded when the interim defense minister, Velizar Shalamanov, broke all taboos by presenting a report on the threat posed to the country by Russian propaganda, guerrilla tactics and cyber warfare.

Checking out of NATO

Shalamanov took up his role shortly before a major NATO summit in Wales, only to find that Bulgaria's previous Socialist administration had effectively checked out of NATO. "The minister of defense didn’t participate in [ministerial summits]," Shalamanov said. "They were not aware what the agenda of the [NATO] summit in Wales was. [There was] no preparation."

"[Bulgarians] have always this soul-searching between eternal gratitude and resentment" — Georgi Pirinski, MEP

Shalamanov thought it unlikely that Radev would win the presidency but said there was a serious risk of Bulgaria backsliding within NATO if he did. "Nominally we will stay in NATO but first of all they will have no interest in NATO and second there will be no trust from NATO in Sofia."

Bulgaria is nowhere near as anti-Russia as other former Warsaw Pact countries such as Poland. In popular eyes, Russia is still often cast as the liberator from the Turks in 1878.

"[Bulgarians] have always this soul-searching between eternal gratitude and resentment," said MEP Georgi Pirinski, a former speaker of Bulgaria's National Assembly and former deputy chair of the Socialist Party.

That was why Plevneliev's speech went down so badly, Pirinski claimed. "Let's say the president's speech was very strong on the Euro-Atlantic commitment. It divided the [European] Parliament: half applauded, the other half did not. [The reaction] was even stronger in Bulgaria."

Pirinski described how EU and NATO membership were presented to Bulgaria as a package. "You wish to be a member of the EU, that cannot happen without joining NATO," he said. "This was a way to fit into the new world order, where joining NATO would not mean distancing from Russia. [Now] there is no partnership between NATO and Russia. Much of the hope of joining Europe has not materialised."

Although most analysts expect that a strong center-right GERB candidate would win the presidency, Vassilev, the former ambassador to Moscow, noted that there was growing suspicion about why prime minister Borisov had not yet nominated a candidate, and whether he would allow the presidency to sway more toward a "Eurasian tilt" to appease Bulgarian oligarchs.

"At the end of the day, however, Borisov's main interest is staying in power — and pushed to the extreme — he is likely to stay on the EU and NATO line," Vassilev said.

Borisov has insisted that GERB will field a heavyweight candidate to defeat Radev by October 2.

Despite that, former Defense Minister Shalamanov noted that Moscow had every reason to assert its influence.

"For [the Russians], success is to prove that NATO is not working well, the EU is not working well and actually Bulgarians made a mistake ... It means they will do everything possible to have an influence on Bulgaria."