Now, after trouncing former Hawaii Gov. Linda Lingle, Hirono is embracing her standing as the state's first woman to serve as senator and the Senate's first Asian-American woman.
Hirono told The Associated Press after winning Tuesday night that the historical footnote says more about the makeup of the country's electoral pipeline.
"What it reflects is that we need a lot more diversity in the United States Senate," said Hirono, who was born in Fukushima, Japan. "I'm going to do my part to support more women to run for Congress and certainly support more minority candidates."
Hirono, 65, moved to Hawaii with her mother in 1955, then went on to practice law in Honolulu before she was elected to the Hawaii Legislature in 1980. She was elected as lieutenant governor in 1994 and 1998, then lost a governor's race to Lingle in 2002. She was elected to the U.S. House in 2006, and is generally considered one of its more liberal members.
Hirono ran on a platform of stopping Lingle as a representative of national Republican interests. At every turn in the race, Hirono linked her opponent with well-known GOP names including Mitt Romney, Paul Ryan and George W. Bush.
Hirono held court for Democrats in a state known to support the party. President Barack Obama topped the ticket for Democrats in his birth state in his bid for re-election.
While Hirono didn't win as much support as Obama in the state, she beat Lingle with nearly 62 percent of the vote compared with nearly 37 percent for Lingle.
Hirono has followed other Democrats on several issues, including Obama's jobs plan and health care reform.
Democrat Joe Donnelly is a three-term congressman from northern Indiana who ran as a centrist highlighting his support for extending the George W. Bush-era tax cuts while fending off attacks over his support for the federal health care overhaul.
He was born in Massapequa, N.Y., and received bachelor's and law degrees from the University of Notre Dame in South Bend, Ind. He worked as an attorney and ran a printing business before defeating Republican Rep. Chris Chocola in 2006. He had lost to Chocola him two years earlier.
Donnelly entered the U.S. Senate race after GOP-controlled redistricting moved a couple strong Republican counties into what had been a swing district.
The Senate race turned in Donnelly's favor after Republican Richard Mourdock said in a debate that pregnancies resulting from rape are something "God intended." Donnelly, meanwhile, twice supported a bill that would have denied federal abortion funding even in cases of rape and incest.
Donnelly positioned himself during the campaign as a bipartisan problem-solver against the tea party-backed Mourdock, who defeated longtime Sen. Richard Lugar in a contentious Republican primary.
Donnelly, 57, and his wife, Jill, have two children.
When asked about his vote of the federal health care law, he told the story of his daughter, who takes Enbrel for her rheumatoid arthritis, at a price tag of $1,500 a month. Donnelly says he worried about people who can barely pay their rent being able to afford such drugs.
"How do they make it so their daughter doesn't have to go in a shower stiffened up every single day, as opposed to being able to get this prescription?" he said.
Independent Angus King may be just starting out in his new role as a U.S. senator, but he's long been a well-known figure in Maine whose independent politics have been his calling card.
The 68-year-old King was Maine's governor for two terms between 1995 and 2003, establishing credentials as someone who could work with both parties. Before that he spent 18 years as a public broadcasting commentator on state public policy issues.
Angus Stanley King Jr. was born in Alexandria, Va., grew up there in a politically active family, and after law school at the University of Virginia came to Maine as a lawyer serving low-income people.