Hillary Clinton named Virginia Sen. Tim Kaine as her running mate for the Democratic presidential ticket, a widely anticipated choice that may say more about how she wants to govern than how she plans to win in November.

Clinton made the announcement Friday in a text message to supporters. ¡°I¡¯m thrilled to tell you this first: I¡¯ve chosen Tim Kaine as my running mate. Welcome him to our team,¡± it said. In a message on Twitter, Clinton said Kaine has dedicated his life to fighting for others, and described him as ¡°a relentless optimist.¡± The pair were to appear Saturday in Miami.

Clinton called Kaine at 7:32 p.m. Washington time to make it official, according to a campaign official, who asked for anonymity. Clinton then spoke with President Barack Obama.