I googled average age of democrats in office versus age of republicans in office. Some interesting links...
https://www.bing.com/search?q=average+age+of+democrats+in+office+versus+age+of+Republicans+in+office&form=EDGNB2&mkt=en-us&httpsmsn=1&refig=7695e31633b3413fd1dbc3864c552fea&sp=-1&pq=average+age+of+democrats+in+office+versus+age+of+republicans+&sc=0-61&qs=n&sk=&cvid=7695e31633b3413fd1dbc3864c552fea
I suspect both parties go down a bit this incoming January. The senate though probably not.