US President Joe Biden secured a decisive victory in the South Carolina Democratic primary on Saturday, expressing confidence in defeating his Republican rival Donald Trump in the upcoming November election.

The 81-year-old incumbent Biden initiated his journey toward securing his party's nomination with a commanding win, leaving his two distant rivals far behind, as indicated by projections from US media. However, Democrats will closely analyze the primary results to assess if Biden, grappling with diminished approval ratings, managed to secure the support of African-American voters who played a crucial role in propelling him to the White House four years ago.

"Now in 2024, the people of South Carolina have spoken again and I have no doubt that you have set us on the path to winning the presidency again -- and making Donald Trump a loser -- again," Biden said in a statement.

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The southern US state played a pivotal role in launching Biden's successful campaign for the White House in 2020. He managed to turn his campaign around after facing setbacks in earlier primaries.

In the current primary, Biden faced only two long-shot challengers: Minnesota congressman and gelato magnate Dean Phillips, along with best-selling self-help author Marianne Williamson. However, there were concerns about voter turnout, as observed by AFP at polling stations in the historic city of Charleston. Many people perceived Biden's victory as a foregone conclusion, resulting in only a trickle of voters.

Fewer than 40% of US voters believe Biden worthy of reelection: poll

A Gallup survey released two days ago found that less than 40% of American voters feel US President Joe Biden deserves to be reelected.

His public favor rating has been below 50% since August 2021, raising concerns among his fellow Democrats as he prepares for a rematch with Republican former President Donald Trump in November.

The poll indicated that "the 38% of voters who say Biden deserves a second term is slightly lower than the 41% of Americans who approve of the job he is doing in the same survey."

The large majority of Democrats (82%) believe Biden should be reelected to the president, as do 29% of independents and 3% of Republicans.

Concerning congressional elections, the 24% who think members are worthy of reelection is lower than in all former elections except in 2012 when only 20% thought so.