LAS VEGAS, USA (REUTERS) - Mrs Hillary Clinton is turning on the charm in Nevada in order to drum up support from the state's minority groups.

The Democratic caucus this Saturday has emerged as an unusually important test for her and her opponent Bernie Sanders. Civil rights leader John Lewis joined Mrs Clinton in her campaign rally as she called on people to nominate her.

"Bring your friends, your neighbours, your family and I promise you, I promise you I will work my heart out every single day to make progress that are contrary to make us proud," said Mrs Clinton. "To give us all the opportunity that we should have. And I get that every child a chance to live up to his or her God given potential. Thank you all so much."

While Mrs Clinton is under pressure to keep her lead among Latinos, Mr Sanders has to make headway to show he doesn't solely rely on the young white voters who make up the core of his support base. Latinos make up more than a quarter of Nevada's population.

Mr Sanders said: "Everything in my political gut tells me that we have the momentum here in this state; that if people come out in large numbers on caucus days we're going to win here in Nevada."

Both candidates have been canvassing door to door as many residents lost their homes in the financial meltdown of 2008, and their phone numbers haven't changed in the Democratic database.