The trade involves the currencies of Mexico and Russia, the two emerging markets thought to be most affected by Trump’s foreign policy. In 2016 investors were buying the ruble and selling the peso in expectation the Republican candidate would mend relations with Russian President Vladimir Putin and cut trade ties with Mexico after winning the election. This time around, the trade has reversed as Joe Biden gains in the polls.

“Trump is very keen to ingratiate himself with Russia, so what’s good for him is good for Russia,” said Paul McNamara, who oversees $4.5 billion in emerging-market debt as a money manager at GAM (UK) Ltd in London. “Biden looks more likely to go back to a rules-based global trade regime, with Mexico and China potential beneficiaries.”

The peso has rallied more than 6% against the dollar in the past three months, the best performance among major emerging-market currencies, as investors bet that increased stimulus under a Biden presidency will help boost Mexican exports to the U.S. The ruble has slumped almost 8% in the same period, with markets predicting that a Democrat in the White House will more likely impose harsher sanctions on Russia.

Not everyone is on board. Sergei Strigo, a London-based money manager at Amundi (U.K.) Ltd. says this year’s election is too unpredictable to create any trading opportunities. In 2016 he was buying the Russian currency and selling the peso, but this year he has an overweight position on the Mexican currency, and has used the recent sell-off to add to his ruble overweight. Amundi manages over 40 billion euros ($47 billion) in emerging-market assets.

Other factors are at play. A rally in global oil prices helped the ruble in 2016, while a slump this year has hurt the Russian currency without harming the peso. Meanwhile, interest rate cuts have made ruble bonds less appealing to foreign investors.

Sanctions Risks

The aftermath of the last election is proof that using currencies to predict the outcome is tricky. Back then, the ruble continued to surge into 2017 before crashing as Trump became mired in allegations of Russian meddling in his campaign. Putin said this week that a bipartisan consensus in the U.S. on the need to contain Russia had meant Trump’s presidency wasn’t as beneficial to Russia as expected. The Trump administration imposed or expanded sanctions 46 times on Russia, more than any previous one, he said.

Most analysts and investors still agree that a Biden presidency isn’t likely to mark a big improvement in U.S.-Russia relations. A multitude of new sanctions risks have surfaced since the poisoning of opposition activist Alexey Navalny using the banned nerve agent Novichok, which was also used on former Russian military officer Sergei Skripal in the U.K. In 2018. The Kremlin has also been criticized for supporting for embattled Belarusian leader Alexander Lukashenko after a disputed election.

“Biden would be more likely to use sanctions with regard to the perceived misbehavior of Russia in the past U.S. elections, the Skripal case, the Belarusian elections and support to Minsk, and the Navalny poisoning,” said Cristian Maggio, head of emerging-markets strategy at TD Securities in London.