By the narrowest of margins, the U.S. Senate on Wednesday afternoon confirmed Suffolk County District Attorney Rachael Rollins as the next U.S. attorney for Massachusetts.

The Senate was deadlocked 50-50 along party lines, requiring Vice President Kamala Harris to break the tie and declare Rollins confirmed as the top federal prosecutor for the Bay State.

Nominated by President Joe Biden in July, Rollins became the subject of a non-traditional confirmation process with Republicans, led by Arkansas Sen. Tom Cotton, holding up her nomination in the Judiciary Committee and forcing Democrats to take what U.S. Sen. Ed Markey has said would be the first roll call vote on a U.S. attorney nominee since 1975.

Rollins' confirmation means that Gov. Charlie Baker now will get to appoint a new Suffolk County district attorney to serve out the last roughly one year of Rollins' initial term. In an April tweet, Rollins said, "FYI, when DA's leave, at least all the men that did before I was elected, they recommend (tell) the Governor who should replace them."

Rollins, who will be the first Black woman and just the second woman to be the state's U.S. attorney, worked in the office as an assistant U.S. attorney from 2007 to 2011 before taking on general counsel positions at the state Department of Transportation and Massachusetts Port Authority.

In 2018, the reform-minded Rollins came out on top of a five-person Democratic primary for Suffolk DA with 39 percent of the vote, then captured 80 percent of the vote in the general election.