Democratic presidential hopeful Biden aims to keep Nevada on his side

Democratic U.S. presidential candidate Joe Biden, who wears the nickname "working class Joe" with pride and courts a multi-racial voter base, faces a stern test of his ability to win nationally in Nevada's mining towns and unionized gambling parlors.Nevada's Feb. 22 nominating contest is the third one in the state-by-state process of picking a Democratic nominee to face Republican President Donald Trump in the Nov. 3 general election.The former vice president's advisers have said Biden's strengt