DETROIT - Hillary Clinton has faced surprisingly strong competition this primary season, and she's been bombarded with criticism. But she has maintained a strong bond with one significant bloc of Democratic Party voters.

Black women, who were part of President Barack Obama's winning coalition in 2008 and 2012, have locked arms behind Clinton. They're hailing her as a Democratic standard-bearer, survivor and friend.

Though the primary contest is not over, the former secretary of state holds a big delegate lead over Vermont Sen. Bernie Sanders and is considered likely to win the Democratic nomination. African-American women have played a big part: About 8 in 10 across all the states where exit polling has been conducted have voted for her. And in some cases support has been above 90 percent.