Sullivan led Begich by about 8,100 votes on election night last week, and when state officials counted absentee and questioned ballots Tuesday, the results indicated that Begich could not overcome Sullivan's lead.
The Alaska seat was initially considered key to Republicans' hopes of taking control of the U.S. Senate, but that was accomplished election night with GOP victories in other states.
Sullivan, a first-time candidate, ran a confident campaign, ignoring the debate schedule Begich released during the primary and setting his own agenda. He also attracted some star power to the state, with Texas Sen. Ted Cruz, a tea party favorite, and 2012 GOP presidential nominee Mitt Romney rallying support for Sullivan in the waning days of the hotly contested race.
Sullivan pledged to fight federal overreach, talked about the need for an energy renaissance in the U.S. and, at seemingly every opportunity, sought to tie Begich to President Obama and Senate Democratic leader Harry Reid, who are unpopular in Alaska.
Begich complained that Sullivan offered little in the way of proposals for what he would do as senator. Begich also tried to paint sharp contrasts between himself and Sullivan in areas such as women's health, education and Alaska issues.
Begich, for example, was born and raised in Alaska. He cast Sullivan, who grew up in Ohio, as an outsider, and many of the early attacks by pro-Begich groups keyed in to that theme. That perception of Sullivan made for an at-times uncomfortable debate on fisheries issues, in which questioners grilled Sullivan about his knowledge of one of Alaska's most important industries.
On several occasions, Sullivan's wife, Julie Fate Sullivan, an Alaska native and frequent companion on the campaign trail, appeared in ads defending her husband's ties to the state and his positions on women's issues.
Sullivan has roots in Alaska dating to the 1990s but was gone for nearly seven years for military service and work in Washington that included working as an assistant secretary of State. He returned to Alaska in 2009, when he was appointed attorney general by then-Gov. Sarah Palin.
He most recently served as Alaska's natural resources commissioner, a post he left in September 2013, to make his first run for public office.
Sullivan hit the ground running, exhibiting a fundraising prowess that rivaled and during some quarters exceeded that of Begich. Many of his supporters cited his service in the Marine Corps reserves or the oft-repeated GOP refrain that became of a hallmark of the campaign -- that Begich voted with Obama "97% of the time," a figure that takes into account votes during 2013, many of them on confirmations, on which Obama stated a preference.
Sullivan said he was humbled by the support he received and publicly sought to tamp down expectations, even as campaign members expressed great confidence in a victory in the lead-up to Tuesday and said Democrats' much-talked-about ground game wasn't all it was made out to be.
Tens of millions of dollars were pumped into the state, with Republicans seeing Begich as vulnerable and Democrats trying to hold the seat Begich won in 2008. Voters were barraged by calls and ads, which many said they were turned off by.
Sullivan emerged from a hard-fought three-way GOP primary to take on Begich, who had token opposition. Begich focused during that race on bolstering his homespun image, casting himself as an independent thinker unafraid to stand up to Obama, and as a lawmaker with a record of working across party lines, including with Alaska's senior senator, Republican Lisa Murkowski. Murkowski, who backed Sullivan after the primary and is in line to chair the Energy and Natuarl Resources Committee when Republicans take over the Senate, told Begich to knock it off.
A turning point, in the view of many observers, came shortly after the primary in an ad from Begich's campaign that painted Sullivan as soft on crime. It featured a man identified as a former Anchorage police officer standing outside the home where an elderly couple was beaten to death and a family member sexually abused in 2013. It ended with the man saying Sullivan should not be a senator.
The ad, which Sullivan responded to with one of his own, was pulled following a demand from an attorney for the victims' family.
Begich, in discussing the ad, said Sullivan had a "pattern when he was attorney general of doing these plea deals that let violent offenders, sexual offenders out earlier than they should be." He said Sullivan's record as attorney general needed to be scrutinized, but that didn't become a major focus of TV ads by his campaign and surrogates.
Instead, some of the strongest criticism of Sullivan was in regard to his residency, his support of a permitting bill that critics said would have limited public participation in the state's permitting process and his stance on abortion.