WASHINGTON

Voters are heading to polls in 15 US states and one territory to cast their ballots in presidential primary elections on Tuesday, widely known as Super Tuesday.

States where both Republicans and Democrats will cast ballots include Alabama, Alaska, Arkansas, California, Colorado, Maine, Massachusetts, Minnesota, North Carolina, Oklahoma, Tennessee, Texas, Utah, Vermont, and Virginia. Citizens in American Samoa will also vote.

The primary election process, which started this January in Iowa, is where Democratic and Republican party candidates compete to become their party's presidential contender, and is set to officially end on June 8, though the winners are expected to be crowned long before that.

The parties' presidential candidates will be officially chosen at the Republican National Convention in Milwaukee, Wisconsin on July 15-18 and at the Democratic National Convention in Chicago on Aug. 19-22.

Super Tuesday, the day the largest number of states hold their primaries, has been a pivotal day in American politics since the 1984 presidential elections.

Super Tuesday will allocate more than one-third of the total delegates up for grabs in both the Republican and Democratic presidential primaries.

With the Democratic Party having already determined Joe Biden's candidacy, attention this year is focused on the Republican Party and its leading contender, Donald Trump.

The former president is expected to emerge from Super Tuesday with a comfortable and decisive victory over his only remaining rival, former South Carolina Governor Nikki Haley. The outcome will likely solidify his position as Biden's opponent in the fall presidential election, set for Nov. 5.