Of course Senator McConnell is to blame that he did not insist on super majority requirement like dingy Harry Reid did.
There was a heck of a lot they could have done by not cooperating with Obama on matters like the budget. But they just rolled over and lost all bargaining power. And Obama has just ignored them ever since, either just claiming he has the excutive right to do what he wants, or essentially steamrolling Democrat bills through which they can’t stop because they gave up their power (example, what just happened in terms of the latest stop-gap spending bill.
The other thing they could have done was invoke the nuclear option and say the rule prohibiting it was no longer in force because the Democrats had already broken the rule.