Irving Ives was no longer in office, having retired from the Senate in 1959 due to ill health.
Jacob Javits was Jewish. This is a nonstarter for a national candidate in the year 1960.
Kenneth Keating was a Catholic with less than two years tenure in the Senate, elected to Ives' seat.
Putting a Catholic on the ticket as VP would be seen as pandering to the Catholic vote as a counter to Kennedy's religion and might turn off Christian fundamentalist voters in the Midwest and border states. He had no political following, was not a particularly effective campaigner and I question his ability to swing NY to the GOP. His short time in the Senate would negate Nixon's "Experience Counts" campaign platform.
No. only Rocky had the (possible) ability to swing NY to the GOP, and he had no interest whatsoever to being Nixon's VP. Indeed, Rocky hoped Nixon would lose so he could run in 1964.
Kenneth Keating had over a decade of experience in the House, as a staunchly anticommunist, liberal Republican who had his own talk show, which made him pretty popular among House Republicans.
Ha! Javits was very popular - he beat Wagner, the well-liked Mayor, for Senate, Andy’s was the leader of Republican Senate liberals. His Jewish heritage would not hurt him much, if at all. I mean, it wasn’t even too controversial to appoint a Jewish SCOTUS Justice in 1916. Why would that be controversial in 1960?