It was Pence's second time breaking a tie on Wednesday. Earlier, he had raced to Capitol Hill after a 49-49 tie to end a filibuster of Brownback's nomination. He was again needed to vote later in the day on the final confirmation vote, 50-49.
Republicans control 51 seats in the chamber but two GOP senators were not present to vote: Sen. John McCain, who's battling cancer in Arizona, and Sen. Bob Corker of Tennessee, who's in Davos, Switzerland, for the World Economic Forum.
Throughout the tax reform battle in the fall, Democrats often cited tax cuts in Kansas -- which Brownback supported -- that were later repealed after the state's economy struggled. Brownback, a former senator himself, had been seen on Capitol Hill in recent months lobbying senators to back his nomination.
Democrats had also brought up concerns about Brownback's confirmation hearing in October. At the time, Sen. Tim Kaine of Virginia asked Brownback if there was any circumstance in which religious freedom could justify "criminalizing, imprisoning or executing" someone based on sexual orientation.
"I don't know what that would be, in what circumstance, but I would continue the policies that have been done in the prior administration in working on these international issues," he said.
Sen. Bob Menendez, D-New Jersey, argued on the Senate floor Wednesday that Brownback's answer was insufficient.
"Governor Brownback could not bring himself to muster a resounding 'no,' " Menendez said. "Condemning such horrific human rights abuses should never be a heavy lift for anyone who seeks to represent our nation on the global stage."
According to The Kansas City Star
, Brownback later clarified his answer in a written response
"Violence or persecution in the name of religion against members of the LGBT community is wrong, as is persecution or violence based on gender, race, faith, age, heritage, national origin, or disability," Brownback wrote.
As Sen. Orrin Hatch, R-Utah, headed into Brownback's confirmation vote, he was asked about the opposition to Brownback, which is unusual for nominees who are former senators.
"Sometimes politics trumps friendships around here," Hatch said. "And it shouldn't."
As president of the Senate, the vice president has a unique relationship with the upper chamber and can cast a tie-breaking vote in the rare event the Senate is evenly split. Since the 1870s, each vice president has done this fewer than 10 times during his tenure
While Pence has been vice president, Republicans have maintained a thin margin over Democrats in the Senate, which increases the likelihood of a tie. For all of 2017, Republicans numbered 52, compared with Democrats at 48. That balance changed to 51-49 in January, after Democrat Doug Jones was sworn in following his victory in the December special election in Alabama.
Tie-breaking votes are also more common now because the threshold for passage on procedural votes like the one Wednesday was lowered from 60 votes to 50 in 2013, essentially creating more opportunities for a tie.