The Senators don't seem to understand how Silk Road works; Bitcoin will be an even bigger stretch for them. Help them see that Bitcoin isn't about drugs and money laundering.
It's worth a try.
They do however understand not to type the name Bitcoin or Tor anymore because they know the more people find out about it and start using it the more resilient we get

They say any press is good; that's one upside to this. Bitcoin is about to see some Streisand effect.
For Bitcoin to gain mainstream adoption, legality is important. Most people won't touch it, if it's banned in their country.
Politicians react to voter pressure. Even if people think that they don't care about the constituency, the Senators still want to keep their jobs. These two are probably hoping for some "tough on drugs" voter credits.