Considering the fact that Republicans routinely romp in Tennessee by anywhere from 20-50 points, an 11 point win would actually be excellent evidence of a Democratic wave.
But yes, this race is safe R, unless it turns out that Blackburn is a pedophile.
I wouldn't be too sure about calling this race safe R. It's over 10 months until the election and ten thousand things can happen between now and then. I'd probably say lean R for now, this race could get as close as 2006.
Yeah, here's a few of those 10,000 things that could lead to Blackburn losing: Her being a pedophile, her being a murderer, etc. But if we're going to start considering 0.01% probabilities, then hardly any race is truly safe.