ABC News projects that Elizabeth Warren, the Democratic Senate candidate in Massachusetts, will win her race, picking off a Republican seat for the Democrats in the battle for control of the Senate.
Billed as one of the most important races in the fight to control the Democratic-led Senate, the contest pitted Warren against Sen. Scott Brown, the incumbent who shocked the political establishment in 2010 with his victory in a special election to fill the seat that the late Sen. Ted Kennedy held for 47 years.
Warren becomes the first woman elected to the U.S. Senate from Massachusetts.
CLICK HERE for ABCNews.com's live-streaming Election Day coverage starting at 7 p.m. ET.
This is the year that Kennedy would have been up for re-election, so Brown was up again a mere two years after his first win.
Brown, 53, and Warren, 63, engaged in what was the year's most expensive Senate race for spending by candidates only, according to the Center for Responsive Politics. The campaigns had spent more than $70 million collectively by mid-October.
More remarkable: The race was almost entirely absent any outside spending, the result of an agreement between the candidate's called "The People's Pledge," which vowed to keep outside ads out of the hotly contested race.
Find election-night results for presidential, Senate and House races HERE.
Those familiar with Massachusetts politics, including Brown himself, always expected Democrats to mount a serious attempt to take back the seat this time around.
The wild card was who would jump in to challenge the freshmen senator. That candidate turned out to be Warren, a professor at Harvard Law School and creator of the Consumer Financial Protection Bureau, a newly formed, federal department that developed under the Obama administration.
With a good level of name recognition established as a result of her work with the agency, as well as her oversight of the Troubled Asset Relief Program (more commonly known as TARP) and a lengthy resume, Warren was the Democrats' answer to the much-considered question of who could challenge the popular senator.
Warren announced her candidacy in September 2011, and the race was fierce from then on.
The conversation in the Senate race mirrored the presidential race, with Brown attacking Warren for comments she made in 2011 when she said "there is nobody in this country who got rich on his own." The comments mirrored Obama's "you didn't build that" remarks in July on which Republicans pounced.
Brown launched a "Thank You for Building This" tour as part of his campaign's efforts to highlight the senator's support for free enterprise. Brown kicked off the tour in early August by bringing coffee and donuts to a construction crew in Framingham, Mass.
Warren didn't back down from her comments, however. Indeed, the first-time candidate made infrastructure a big part of her proposed policy agenda, launching her "Rebuild Now" tour that called for an investment in the country's infrastructure.
Warren's unapologetic support for such government investment has helped to make her a rising star within the Democratic base.
Brown has assailed Warren for listing her herself as "Native American" on law school documents early in her teaching career.
"Elizabeth Warren said she was a Native American, a person of color," Brown said at their first debate in September, gesturing toward Warren. "As you can see, she's not."
Polls showed the race to be a virtual dead heat until the end, when Warren started to pull ahead in the deep-blue state in the final weeks.