Explain a Tom Lehrer joke to me, Please

Cafe Society
1

I’ve recently been having my Amazon Echo play me Tom Lehrer’s songs (it’s been delightful, btw). From the album That Was the Year That Was, when he’s introducing the song “George Murphy,” he makes a joke about how, being from Massachusetts, he feels entitled to some bragging rights, due to the fact that his is the only state with three senators.

Is this some sort of obscure reference to the Kennedy clan?

For reference, the album was recorded in 1965.

TIA.

2

Yes - it’s a reference to Bobby Kennedy, who had been elected as Senator from New York in 1964.

3

Got it in one.

4

Same senatorial seat later filled by Daniel Patrick Moynihan and Hillary Clinton.