Jennifer Hudson sings Happy Birthday to Obama

... but even Marilyn would have struggled with Rahm Emanuel standing next to her (with video)

LAST UPDATED AT 17:01 ON Thu 4 Aug 2011

It wasn't in quite the same league as Marilyn Monroe's breathless rendition of Happy Birthday Mr President, but Jennifer Hudson led the crowd in a spirited singalong as Barack Obama celebrated his 50th birthday at a Democrat fundraiser in Chicago on Wednesday night.

Joining soul-singer Hudson on the stage at the event were Obama's former chief-of-staff Rahm Emanuel, now mayor of Chicago, music producer Herbie Hancock and members of the local band OK Go. Flanked by such a disparate group, even Monroe would have struggled to put on a sexy performance, but Hudson managed to get the crowd behind her.

Obama, whose birthday was actually today, appeared on stage midway through the song and grinned broadly before hugging Emanuel and Hudson. ·