Sinema is the first Democratic U.S. Senator from Arizona since Dennis DeConcini retired in 1995.
Rep. Martha McSally (R., Ariz.) conceded to Democratic opponent Rep. Kyrsten Sinema (D., Ariz.) on Monday evening after after a slow vote count dragged on for almost a week after voters cast their ballots last Tuesday.
The GOP contender conceded Monday after new results showed Kyrsten Sinema's lead statewide is now approaching 38,200 votes. "This is not plausible".
"Arizona voters.made history by electing bold pro-equality champion Kyrsten Sinema as the first openly bisexual U.S. Senator", Griffin wrote in a statement shared online.
Republicans expanded their 51-49 Senate majority by two seats on election night, strengthening their ability to confirm pro-life judges as their loss of the House of Representatives all-but eliminates any prospect of pro-life federal legislation over the next two years.
While Ms Sinema frequently voted with conservatives in the House, her background also stands in contrast to many other members of Congress.
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It was not clear if the burst of violence, which appeared to have subsided early Monday, would derail those arrangements. UN Middle East envoy Nickolay Mladenov said efforts were being made with Egypt to pull Gaza " back from the brink ".
"Arizona rejected what has been far too common in our country - name calling, petty, personal attacks and doing and saying what it takes to get elected", Sinema said as scores of backers waved her purple-and-yellow campaign sign.
She ran promising to be a nonpartisan problem-solver and hitting McSally over her vote to weaken protection for people with pre-existing medical conditions.
But the real star of her concession video is McSally's dog Boomer, a delightfully unbothered golden retriever who upstages McSally with his blissful, tongue-lolling presence, sitting upright next to her on the couch and making a play for a handshake. Democrats still proved they are capable of winning in Michigan, Wisconsin, and Pennsylvania, but the more mixed results in OH and Florida show Democrats have to put more states in play to give themselves cushion - and a competitive Arizona is exactly what they need.
Last month, a 2006 interview with the nightlife magazine 944 also resurfaced, in which Sinema suggested that women who choose to be full-time homemakers or mothers have nothing to be proud of. She cited the example of John McCain, who died in August. A onetime Trump critic, McSally instead allied herself with the president in this contest. Jeff Flake, who declined to seek re-election in the state.
The upheaval comes as Arizona, long a Republican bastion, emerges as a swing state in presidential elections. Mr Rohrabacher was one of most vocal supporters of Russian Federation and its President Vladimir Putin in Congress.
Now that Sinema has won, Democrats have a way forward, and hope for the future.