No, actually the Senate can change the rules anytime they want on a simple majority vote.
time to FREEP all of our pubbie reps! And don't be polite about it. Send 'em a box of Jello and tell 'em to put some spine into it (better just send a PHOTO of Jello. These days, you'd be sitting in jail for a couple years while they determined if or not the Jello powder was a safe substance.
No it takes a supermajority to outright change Senate rules mid-session.
That's the whole point of the "nuclear option"
Frist could have adopted new rules by majority vote when the 109th Congress first met, but not now.
In order to implement the nuclear option, cloture has to fail, and a point of order must be raised.