According to a statement provided by the Deputy Senate Sergeant at Arms, Martina Bradford, the U.S Senate has, indeed been attacked for the second time in a row. Responsible for the security of the Senate office, the Sergeant at Arms also added that the hackers were unsuccessful in laying their hands on any specifically sensitive data, as such. Having said that, there isn't any word on what data was stolen, either.
They also went on to add that till now they have managed to stay ahead of the hackers, as also keep them away from the main Senate network. This attack comes after a hack of a similar nature gained prominence over the weekend. Lulz Security, the hacker group that has many other such hacks to its credit claimed responsibility for the first hack. However, no one has claimed responsibilty for this attack yet.