Victoria Buckley, 51, a welfare mother and battered woman who rose to become Colorado's secretary of state and the nation's highest-ranking black female Republican in a statewide office, died July 15 at a hospital in Denver after a heart attack.

Ms. Buckley was a controversial figure in Colorado, where she consoled survivors of the Columbine High School shooting while vigorously defending the National Rifle Association. Critics assailed her performance as secretary of state, citing poor management of the office where she first began working 25 years ago as a clerk.

But she was considered a bright light on the national Republican scene and was expected to play a role in the upcoming Republican National Convention.

"Her story is a model for those wanting to climb out of poverty and improve their lives," said U.S. Sen. Ben Nighthorse Campbell (R-Colo.).

Ms. Buckley, a Denver native, was a civil servant and political unknown when she stunned the state's political establishment by winning the secretary of state election in 1994.

That victory came after she had weathered many personal trials: unwed motherhood when she was 20 and three failed marriages, including one to a man who beat her even while she was pregnant. She struggled as a single parent of three and for a time survived on welfare.

As secretary of state, Ms. Buckley stressed improving customer service and won praise for returning $9 million to the state treasury from office fees. But within a few years, critics were carping that the office was poorly run. Her office became the target of a state investigation after she awarded a lucrative consulting contract to a campaign adviser.

After the school shootings in Littleton, Colo., she spoke at the funeral of Isaiah Shoels, a black athlete who was one of the 13 youths gunned down by two Columbine High students.

But Ms. Buckley, an NRA member, also spoke at the NRA convention held in Denver less than two weeks after the Columbine massacre. She was the only state constitutional officer to address the group, which cut short its annual meeting that endured anti-gun protests in the wake of the tragic shooting deaths in April.

Ms. Buckley was to be featured in a Republican National Committee advertising campaign this year that urged blacks to join the Republican Party. But she demanded that her picture be removed from the ad because she felt it treated her as a token.

Survivors include three sons, her parents and a sister.