Hi Todd,
Haven't tried it yet, below are some points of consideration.
If you have SQL 2014 ready, you can create a data server and test a query to check if it works for 2014.
Also, from the post below, you should be able to access SQL 2014 from same jdbc.
Supported JDBC Drivers for MS SQL Server - DbVisualizer
But again as you are running on Server 2003, jdbc 4.x may not support as it does not meet system requirements. PFB:
Download Microsoft JDBC Drivers 4.1 and 4.0 for SQL Server from Official Microsoft Download Center
Hope it helps. Do let us know what works out for you. Thanks in advance.
Best Regards,
Swaroop