Last Updated Jul 22, 2016 11:07 PM EDT
Hillary Clinton announced Friday on social media that Virginia Sen. Tim Kaine was her pick to be vice president.
In the message -- sent at 8:11 p.m. ET on Friday night -- Clinton wrote, "I'm thrilled to tell you this first: I've chosen Sen. Tim Kaine as my running mate."
Kaine, for his part, seemed equally thrilled.
Top Clinton aides had promised supporters they could be the first to officially know -- before the press -- and it seems they may have been.
A top Clinton campaign official said that Clinton called Kaine Friday night at 7:32 p.m. ET to inform him that he was her pick. She also spoke with President Obama 16 minutes later to inform him she had selected Kaine.
Kaine was one of a group of two dozen contenders Clinton considered. In April, after the New York primary, her campaign chair, John Podesta, dropped off a Duane Reade plastic bag filled with two dozen binders -- one for each candidate -- with Clinton at her home in Chappaqua.
The rally last week with Kaine in Virginia on Thursday was an opportunity for her to see what a ticket with him would be like.
Clinton, according to the official, enjoyed the rally with him and in particular, liked Kaine's down-to-earth campaign style. After the rally, Clinton invited Kaine back to her Whitehaven Washington, D.C. home. Though the meeting initially included aides, it turned into a one-on-one meeting that lasted about an hour and a half.
The next day, Clinton met with several other potential running mates -- also at Whitehaven -- but it was Kaine that she invited back. On Saturday, Kaine returned for lunch with both their families. President Clinton, Chelsea, her husband, Marc Medvinsky, and Kaine's wife, Anne, were all there.
Throughout her vetting process, Kaine was the only person that Clinton met with twice about the vice presidency. In her deliberations, Clinton always came back around to what she saw as Kaine's readiness to do the job, which is what she has always said was her first criteria.
Podesta, who was also her husband's chief of staff and Counselor to President Obama, gave her some advice about her pick. Her vice president, he said, "needs to be someone who, whenever they walk into a room, you are glad to see them and want to have them as part of any conversation." Clinton felt way about Kaine.
Her final decision came on Friday, July 22.
The Virginia senator is not exactly high-profile, but one thing that most say is that he is exceedingly hard to dislike, a point Clinton alluded to in a fundraising email sent out Friday night.
"To know Tim is to love him," she wrote. "When I was talking to people about this decision, I couldn't find anyone -- Democrat or Republican -- who had a bad thing to say about him."
Sen. Jeff Flake, R-Arizona evidently concurs, according to this tweet.
Kaine hails from the perennial swing state of Virginia, where he served as governor and was elected to the Senate in 2012. Many of Clinton's paths to the White House run through Virginia, so sharing the ticket with a relatively popular native of the state could be a big boost.
He also supported Clinton early in the 2016 race, saying as far back as 2014 that the former secretary of state should be the next president. Kaine was involved in the pro-Clinton group Ready for Hillary, giving him credibility with a candidate who prizes loyalty. Since she became a candidate in April 2015, Kaine has repeatedly hit the campaign trail for Clinton -- most recently at a rally in Annandale, Va., earlier this month.
Though considered one of her safest picks -- Kaine has described himself throughout the vice presidential vetting process as "boring" -- his presence on the ticket could help Clinton with one demographic that has been systematically moving away from Democrats: white men. At the same time, he's fluent in Spanish and spent time in his youth volunteering as a missionary in Honduras.
As for Kaine's Senate seat, there's no concern his election as vice president could jeopardize Democrats' hopes of winning back Congress' upper chamber in November: Kaine's replacement would be appointed by Virginia Gov. Terry McAuliffe, a Democrat and longtime ally of the Clintons.
What his addition to the ticket may not do is quiet the progressive wing of the party that backed Vermont Sen. Bernie Sanders in the primary. Those voters undoubtedly hoped for a pick who would more closely represent Sanders' views, like Massachusetts Sen. Elizabeth Warren.
Kaine beat out several other serious contenders for the job, including Agriculture Secretary Tom Vilsack, Colorado Gov. John Hickenlooper and Labor Secretary Tom Perez.
Presumptive Democratic presidential nominee Hillary Clinton and her running mate Sen. Tim Kaine (D-Va.) will appear on 60 MINUTES in their first joint interview. Scott Pelley will conduct the interview, which will be broadcast Sunday, July 24 (7:00-8:00 PM, ET/PT) on the CBS Television Network.