The White House is looking to Sen. Mark Warner (D-Va.) to help thaw out its frosty relationship with Sen. Joe Manchin (D-W.Va.) in hopes of resurrecting President Joe Biden's Build Back Better plan.\nSubscribe to POLITICO Playbook.\nRaghu Manavalan is the host of POLITICO's Playbook.Jenny Ament is the executive producer of POLITICO Audio.