Ok seems 32 is the high (notwithstanding inauguration dates) of the 50 state era.
Since the 2014 election (+ 2 net), we’ll maintain the number of 31, exchanging LA for KY this year.
After 1994 was just 30, we picked up LA in 1995, and gained Arkansas in July 1996 when Huckabee replaced Jim Guy Tucker in Arkansas. The ‘96 (exchanged NH for WV) and ‘97 (no change, held VA and NJ), elections maintained that number of 32, 1998 reduced it by 1.
We also had 32 after the 1969 elections (gained VA and NJ) until the 1970 election when the dems scored a big net gain.
Gotta go back to the 20’s to maybe have more than 32 (of 48). Party high in terms of percentage was certainly after the Civil war with the Southern states being readmitted and going GOP, that was also the democrat nadir in Congress.
I believe the high mark was 34 GOP Governors after the 1920 elections (48 states). Plummeted to 22 with the disastrous 1922 midterms. 24 in 1924. 26 in 1926 (I’m not making this up, 3 elections in a row with the GOP winning the same number as the year !). 29 were in office in 1929.
1930 dropped to 20. 1932 dropped to 8(!). 1934, 9. 1936, the nadir of the 20th century: 7 out of 48. Regained 10 in 1938 to 17 out of 48.