Not really. What states am I ignoring? D.C was listed #1, so they're already counted a "D" heavy. Illinois has been dominated by Democrats, as has NY.
What, Louisiana? They've had 2 democrat senators from 1884 - 2005. It wasn't until 2005 that a Republican won a Senate seat and not until 2015 did they have 2 seats. In the house, the Dems dominated the ranks until 1993. Since 1971, there have been 7 Democrat governors and 3 Republican's. You're going to tell me that Louisiana from 1971 to 2018 was predominately Republican? I don't think so.
Since 1995, the Republicans dominated the house & senate in Tennessee, but prior it was Dems. Since 1971, there have been 5 Republican governors and 3 Democrat. At best, that's 60/40 Republican.
Cali, Texas, and Florida were also listed. Florida isn't as "R" as you think it is. Since 1971, Dems have occupied at least 1 Senate seat EVERY year, until this one and occupied both for 10 of those years. This year is the first time since 1875 (yes 1875), that both seats were held by a Republican. Prior to 1993, the Dems had a bigger role in the Senate, since it's be Republican's. The last 4 governors (since 1999), are Republican, prior though, from 1971 to 1998, there were 5 Democrats and 1 Republican. At best, we're talking 55/45 Republican.
Texas? Democrats dominated the house prior to 1999 and the Republicans have a small edge since. Since 2013, the Republicans have dominated the House. In the Senate, it was 50/50 from 1971 to 1995. Since, it all Republican. Dominated by Republicans for governor. So, overall, not really dominated by Republican until the last 10 years, but had a small edge in the prior 15. The bulk of the prior 25 years is dominated by the Dems. So, overall, if you want to say they're 55/45 Republican, that's fine.
So in the end, you have 3 states (Tennessee, Texas & Florida) that "slightly lean" Republican, 3 (California, Illinois, & NY) - 4 if you count DC are hard Democrat, and 1 (Louisiana), leaning Democrat. What am I missing?