The Senate Foreign Relations Committee unanimously approved Sen. John KerryJohn Forbes KerryTrump's dangerous Guantánamo fixation will fuel fire for terrorists Tech beefs up lobbying amid Russia scrutiny Overnight Tech: Senate Dems want FCC chief recused from Sinclair merger | Tech rallies on Capitol Hill for DACA | Facebook beefs up lobbying ranks MORE (D-Mass.) to be the next secretary of State earlier on Tuesday, setting up a vote on the Senate floor later in the day. Kerry's nomination later passed the Senate with overwhelming support.

Kerry, the former chairman of the committee, received a voice vote from his colleagues. His nomination had been expected to sail through after Republicans urged President Obama to nominate him instead of Ambassador to the United Nations Susan Rice, after her role in the administration's reaction to the Benghazi attacks last year. 

Patrick will announce his appointment to Kerry's seat on Wednesday. Patrick's former chief of staff, William “Mo” Cowan, and Victoria ­Kennedy, widow of Sen. Edward Kennedy (D-Mass.), are considered frontrunners for the pick. 

Patrick has set the special election primary date for April 30, and the general election for June 25.

Though Rep. Stephen Lynch (D-Mass.) insists he has not yet made up his mind about a run, sources say he is likely to jump into the race soon after Kerry steps down, setting Democrats up for an unwanted primary race. Lynch's flirtation with campaign highlights vulnerabilities some Democrats see in Rep. Edward MarkeyEdward (Ed) John MarkeySenate Democrats introduce bill to block Trump's refugee ban FCC votes to limit program funding internet access for low-income communities Two GOP senators oppose Trump’s EPA chemical safety nominee MORE (D), the front-runner to win the Democratic nomination to succeed Kerry

No Republican has yet officially announced his or her intentions to run for the seat, but Republicans in Massachusetts expect Scott Brown (R) to run again, just a few months after he lost to Sen. Elizabeth WarrenElizabeth Ann WarrenCordray's legacy of consumer protection worth defending Booker tries to find the right lane  Jones raised 0K a day after first Moore accusers came forward: report MORE (D-Mass.)

Secretary of State Hillary ClintonHillary Diane Rodham ClintonO’Malley tells Dems not to fear Trump FBI informant gathered years of evidence on Russian push for US nuclear fuel deals, including Uranium One, memos show Pelosi blasts California Republicans for supporting tax bill MORE has said her last day on the job will be Friday.

--This post was updated at 5:04 p.m.

Alexandra Jaffe contributed.