he answer is yes. There is an example on the demo site. Here is the link . Click on the Estes Park, CO link. Some care has to be given to how it is entered; otherwise, it will not be translated properly when the component create the code to render the marker.
Here is the code inside the marker mentioned above.
“This is a marker with a multi-line description<br /><br /><a href=’http://www.nps.gov/romo/’>Visit Rocky Mountain National Park</a> ”
Notice that the value in the href section contains only single tick marks.