Mexico has began counting votes after an election on Sunday that will almost certainly result in the country's first female president.

The two frontrunners are Claudia Sheinbaum of the ruling Morena party, which is supported by the governing coalition “Let's keep making history” (Sigamos Haciendo Historia), and Xochitl Galvez, who is supported by a coalition of opposition parties.

Jorge Alvarez Maynez, a third candidate, is running on behalf of the Citizens’ Movement.

As the votes began pouring in, Sheinbaum took an early lead, followed by Galvez. This is in line with opinion polls that place Morena's candidate as the clear favorite for the presidential election. There are about 100 million registered voters in Mexico, and about 58 percent of them cast their ballots.

In addition to the presidential election, voters also cast their ballots for about 20,000 offices in this largest election in the country's history.

According to Mexico's National Electoral Institute (INE), these include 128 seats in the Senate, 500 seats in the Deputies, the governorship of Mexico City and governorships in eight states, including Chiapas, Guanajuato, Jalisco, Morelos, Puebla, Tabasco, Veracruz and Yucatan.

According to the latest information from the INE, this is how the three parties fared in the presidential election:

When will we know the final results?

The results are not expected to be available until June 8.

However, on June 2, Mexicans will be able to access the snap count, a statistical forecast that estimates electoral trends based on a random sample of 7,500 polling stations.

On June 2, between 22:00 and 23:00 (from 03:00-04:00 GMT), the INE will announce the results of the snap count of the presidential elections. This announcement will be made in a nationally televised message.

From 8pm (02:00 GMT) on Sunday, the INE will also launch the Preliminary Electoral Results Program (PREP), a system that collects and publishes data recorded by election officials. Al Jazeera will use this data for its vote counter and will also publish the preliminary results when they are announced by election officials.

When will the new president take power in Mexico?

Mexico's newly elected president will take office on October 1, 2024, four months after election day.

This is the first time that the inauguration will take place on October 1 rather than December 1 since a change in the electoral law in 2014.

What other races besides the presidency are being closely watched?

Apart from the question of who will be the country's next head of state, the race for the congressional seat remains crucial.

The ruling Morena party is seeking a two-thirds majority in Congress. This is important for revising the constitution and abolishing what it sees as cumbersome and wasteful control bodies. The opposition, which has joined together in a loose coalition, sees this step as a threat to Mexico's democratic institutions.

This could also affect the peso and investors' reaction to the election.

“If [Morena] “If the Democratic Party wins two-thirds of the vote in Congress, or comes incredibly close to that goal, the decision will be more difficult for investors because it will be a very different scenario in which power is less constrained,” Miguel Angel Toro Rios, dean of the Faculty of Social Sciences and Political Science at Tecnologico de Monterrey, told Al Jazeera.

In Mexico City, the competition is tough: Clara Brugada from the ruling party, Santiago Taboada from the main opposition coalition and Salomon Chertorivski from the Citizens' Movement are in a neck-and-neck race.

Governorships in large, populous states such as Veracruz and Jalisco are also attracting interest.