WASHINGTON — Minnesota Gov. Tim Walz is on a group text called “sports buddies” with dozens of current and former members of Congress, men and women. They mostly trash-talk each others’ favorite teams.

But when Walz gave an interview on MSNBC after President Joe Biden withdrew from the election, that chat became a venue to discuss a different competition: who will be named Kamala Harris’s vice presidential running mate.

“Walz blew it up on MS this morning. He now has to be on the…