Brazilian socialist President Luiz Inácio Lula da Silva and right-wing Senator Flávio Bolsonaro are virtually tied as August comes to a close, according to UBS analysts citing new polling data, turning October's presidential election into a potential coin toss. A Bolsonaro victory would accelerate the eradication of left-wing rule across South America as the continent undergoes a once-in-a-generation rightward political realignment. That shift may also offer an early signal of Europe's upcoming 18-month election cycle, in which right-wing parties and candidates are gaining momentum across several major countries.

Alexandre de Ázara, a managing director and chief economist for Brazil at UBS, told clients on Friday that "the gap is closing" in Brazil's presidential race as Bolsonaro pulls within striking distance of President Lula.

UBS's latest polling aggregator shows Lula taking 44% of valid first-round votes, down one percentage point from Monday's update. Bolsonaro rose one point to 38%, while other candidates remained at 18%.

First round aggregator and polls (% of valid votes for Lula)

First round aggregator and polls (% of valid votes for Flávio)