Republicans are in a very strong position.
Aaron Blake writes at The Washington Post
House
Republicans will control at least 246 out of 435 seats. That's tied for the most since the 1929-30 Congress (the GOP also had 246 seats in 1947-481948-49). And if McSally wins -- she currently leads -- it will be the single biggest GOP majority since the onset of the Depression.
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Senate
Republicans will control 54 out of 100 seats. That's tied for their fourth-highest number of seats since that same 1929-30 Congress, but the larger three were majorities of 55 seats -- i.e. only one more seat.
Governors
Republicans will control 31 out of 50 seats. That's tied for their fourth-biggest number since -- you guessed it -- 1929 and 1930, according to the National Governors Association. But again, the three previous highs were 32 seats -- just one more seat.
State legislatures
Republicans control more than 4,100 out of 7,383 seats -- about 56 percent. That's their highest since 1920, according to the National Conference of State Legislatures. They also control 69 out of the 99 state legislative chambers (including Nebraska, which is technically nonpartisan and has only one chamber, but which is for all intents and purposes under GOP control) -- the highest since at least 1900, which is the oldest data NCSL has.
Margaret Talev writes at Bloomberg:
Republicans are enjoying a five-year peak in popularity after their wins in the midterm elections, according to a new Bloomberg Politics poll, while President Barack Obama struggles with his lowest job approval rating, at 39 percent. The White House also is facing a backlash from independents who oppose his unilateral moves on immigration, and just 24 percent say the country is on the right track, the lowest rating since September 2011.
Obama's weakened standing comes as he and the rising congressional Republican leaders are poised to become partners—or adversaries—in guiding the nation. They will start in January on more equal footing, the poll shows. Forty-five percent of Americans say they now view the Republican Party favorably, while 47 percent hold an unfavorable view. That’s the best showing the party has had since the inception of the poll in September 2009. Opinion about the Democratic Party has plunged, with a favorable rating of 41 percent and an unfavorable rating of 50 percent. This was Democrats’ worst showing in more than five years.
