Behind the Scenes of the DNC: Day 4

Katy Perry practices before her DNC performance Thursday night.  

Media inside Wells Fargo Center for the final day of the DNC. 

Katy Perry sound check before her big performance during the final night of the DNC.  

Katy Perry practices her performance for Day 4 of the Democratic National Convention.  

It's the final day of the Democratic National Convention.  

Day 4 of the Democratic National Convention is about to get underway. 

The final day of the DNC has turned out to be a rainy one .