Former NYC mayor who spent hundreds of millions on unprecedented ad campaign quits after dismal showing in primaries, as race effectively whittled down to Biden versus Sanders

Former vice president scoops up victories on Super Tuesday as party members drift toward seeing him as best alternative to liberal firebrand Sanders

Move comes after billionaire spent unprecedented sums of money in TV ads that got him nowhere on Super Tuesday, though he is still buying new ads and scheduling campaign events

Despite early markers of success, progressive US senator has struggled to win over fan base of Bernie Sanders, leading to poor numbers; says she's not dropping out yet, though

Vermont senator also claims home state, Utah and Colorado; former VP takes Virginia, North Carolina, Oklahoma, Massachusetts, Alabama, Tennessee and Arkansas; no wins for Warren

Leading candidates to face off against Trump look to rack up delegates ahead of party convention; Bloomberg appears on ballots for first time

Former US vice president hopes to turn South Carolina victory into national movement, but also faces challenge by Michael Bloomberg, who is testing his strength for the first time

Biden seeks to consolidate anti-Sanders camp; Bloomberg to find out whether $500 million bet paid off

Democrat candidates are looking to win over electorates with diverse demographics and political ideologies in vote that usually indicates who will remain or drop out of race

Former vice president scores major victory in must-win state, as front-runner Senator focuses on taking big enough delegate lead on Super Tuesday to all but clinch nomination