This is how I resolved this issue:
# service tomcat status
tomcat start/running, process 996
# service tomcat stop
tomcat stop/waiting
# service jenkins status
Jenkins Continuous Integration Server is not running
# service jenkins restart
* Restarting Jenkins Continuous Integration Server jenkins [ OK ]
# service tomcat start
tomcat start/running, process 3839
# service jenkins status
Jenkins Continuous Integration Server is running with the pid 3694
Refresh your browser and Jenkins should be up and running. Hope this helps!