The New York billionaire became Mexico's bogeyman ever since he called migrants "rapists" and drug dealers when he launched his campaign last year.
"The guy is a clown, a blowhard," said Jafet Granados, an 18-year-old biotechnology student who was standing under Mexico City's Angel of Independence monument.
"If he wins, he won't do half of what he has promised."
The government certainly sees risks in a Trump victory.
Finance Minister Jose Antonio Meade said while a Trump victory would undoubtedly cause more "volatility" in the markets, the country was on strong financial footing to deal with it.
And central bank chief Agustin Carstens, who warned in September that Trump could hit Mexico like a powerful "hurricane," said this week that the government had a contingency plan to weather the storm.
With his vows to tear up the North American Free Trade Agreement and make Mexico pay to build a massive border wall, Trump's rise in opinion polls just before the US vote contributed to the fall of the Mexican peso to 19.50 per dollar.
The peso however soared to 18.5563 per dollar in early Asian trading on Monday after the FBI lifted the threat of charges against Trump's rival, Democrat Hillary Clinton, over her use of a private email server while secretary of state.
