Yes, there is a way.
Boot to the operating system, install the Intel® Rapid Storage Technology Console.
And look for the option "create RAID from existing drive" this will allow you to create a RAID without loosing the data.
I have 2 identical drives. When I start RST I have 4 buttons. Status, Manage, Preferences, Help. None of them give me a create option.
If I add a 3rd 1TB drive RST now has a 5th button called Create. I can't find an option to create RAID from existing drive. Under the create option it only shows the 2 empty drives and says pick 2.
Found the problem. Somehow the boot HD had been marked as Dynamic. Used 3rd party software to set it back to Basic and now the Intel software lets me create the RAID 1 using the current boot drive and an empty one. Now at 29% built. Not sure why building the RAID 1 takes WAY longer that cloning the boot drive.