Close Election All the Same
Nixon barely lost to JFK in OTL. JFK narrowly carried Delaware, Hawaii, Illinois, Michigan, Missouri, Minnesota, New Jersey, New Mexico, Pennsylvania, South Carolina, New Mexico, and Texas--Nixon winning between 48-49.9% of the popular vote in each of those 12 states. Nixon narrowly carried Alaska, California, Florida, Montana, Washington and Wisconsin--JFK winning between 48-49.9% of the popular vote in each of those 6 states. Nixon's two-week absence from the fall campaign trail, recovering from a knee injury/infection, and his poor appearance in the first televised debate were two significant reasons given for his defeat.
Governor Nelson Rockefeller as the 1960 Republican nominee clearly eliminates whatever financial advantages that JFK had over Nixon. Rockefeller puts New York's 45 electoral votes (which JFK won in OTL) into play, and perhaps boosts Republican chances in other nearby Northeastern states like New Jersey, Pennsylvania and Delaware. The outspokenly pro-civil rights Rockefeller hurts the Republican ticket in the South, but JFK's Roman Catholic religion did not really cost him any southern states against Nixon anyway. The absence of Nixon from the ticket hurts Republican chances in California, which had a Democratic governor in Pat Brown at that time.
If Rockefeller works hard and spends enough money in the 18 swing states mentioned above, plus New York and Ohio, then he possibly flips enough states from the Democratic to Republican columns to narrowly beat JFK.
On the other hand, Rockefeller was always lazy when it came to campaigning outside New York and relied too much on just his money and name-recognition. Unlike JFK, Rockefeller never worked very hard to win his own party's nomination and expected that it would eventually be offered to him on a silver platter (Goldwaterites out-worked the active Rockfeller campaign in 1964 to win the nomination that year). Plus, as a sitting governor of the then-largest state, Rockfeller had executive responsibilities to distract him from the campiagn trail--unlike both VP Nixon and Senator JFK. Democrats in Albany could be expected to have given Rockfeller a hard time in order to help out JFK. Thus, JFK still might have beaten the less hardworking Rockfeller in 1960.