The joint bid from the United States, Mexico and Canada boasts modern, established stadiums and well-developed transport links, while Morocco is promising a "European" World Cup in Africa, playing on the North African nation's proximity to Europe.
Fifa members vote Wednesday on whether to award the 2026 World Cup to frontrunners North America or to underdogs Morocco, which has African support to bring football's showpiece event back to the continent.
On the eve of the opening match of the 2018 World Cup, delegates from 207 nations attending the Fifa Congress in Moscow are faced with a clear choice.
The joint bid from the United States, Mexico and Canada boasts modern, established stadiums and well-developed transport links underpinned by Mexican football fervour.
Morocco, on the other hand, is promising a "European" World Cup in Africa, playing on the North African nation's proximity to Europe.
But compared to North America, Morocco's bid exists largely on paper -- many stadiums and roads would have to be built and critics question how it would cope with the 2026 tournament, which will be expanded to 48 teams.
Fifa inspectors have classified the North African nation's stadiums, accommodation and transport as "high risk", awarding it just 2.7 out of 5 in an evaluation report, with concerns raised over several critical aspects.
They warned "the amount of new infrastructure required for the Morocco 2026 bid to become reality cannot be overstated".
The report left the US-Canada-Mexico bid as the clear favourite after rating it four out of five.
'Vote on us, not Trump'
But the North American bid fears it could lose out if the vote becomes a referendum on the popularity of US President Donald Trump.
Trump has tweeted threats that if countries did not support the North American bid, they could not expect US support on other issues.
The U.S. has put together a STRONG bid w/ Canada & Mexico for the 2026 World Cup. It would be a shame if countries that we always support were to lobby against the U.S. bid. Why should we be supporting these countries when they don’t support us (including at the United Nations)?— Donald J. Trump (@realDonaldTrump) April 26, 2018
That prompted bid leader Carlos Cordeiro to urge Fifa members to vote on the "merits" of the bid, not Trump.
"We believe strongly that this decision will be made on its merits," Cordeiro said. "This is not geopolitics. We're talking about football and what is fundamentally, at the end of the day, the best interest of football and our footballing community."
The US hosted the World Cup in 1994, while football-crazy Mexico hosted in 1970 and in 1986, the tournament remembered for Diego Maradona's "Hand of God" goal.
Morocco has tried, and failed, four times, most recently in a bid to host the 2010 World Cup, which went to South Africa as the African continent hosted for the first time.
Lost to Qatar
The US lost out to Qatar in 2022 in a vote now tarnished by corruption allegations that spelled the beginning of the end of the once all-powerful Fifa president Sepp Blatter.
It prompted an overhaul of the rules. Whereas previously the 24 members of the Fifa Executive Committee used to determine World Cup races, the host is now decided by a vote of individual Fifa member nations.
In theory, that should make it harder for lobbying groups, or more corrupt tactics, to influence decisions.
But Fifa votes are notoriously unpredictable.
Fifa President Gianni Infantino said on Tuesday: "The important thing is that everything has been done correctly. Now everyone must choose."
Infantino is believed to strongly support the North American bid because the three countries involved backed him for the presidency in 2016 when he took over after the reign of Blatter.
He said on Wednesday that Fifa was "clinically dead" when he took the reins, but that it was now "very much alive".
In a short speech to the Congress, Russian President Vladimir Putin praised Infantino: "We know that (he) became the head of Fifa in difficult times but he has steered it well, like a true fighter," Putin said.
North American bid leaders have promised to deliver a record $11 billion profit -- music to Fifa's ears.
And critics of the Morocco bid point to the fact that the 2026 World Cup will be the first to be expanded to 48 teams, posing an enormous logistical test for the hosts.
Morocco bid leader Hicham El Amrani argues its 12 host cities are "very close to each other, with for example Casablanca a maximum 500km from another venue" compared to the vast distances involved in North America.
The Moroccan bid has enlisted the support of the British communications agency that helped London and Paris land the 2012 and 2024 Olympics.
France, in particular, has lobbied behind the scenes for French-speaking Morocco and the bid has the support of most African nations in line with a call from the head of the Confederation of African Football, Ahmad Ahmad.
But it will likely need heavy support from Europe to pull off a shock win.