Your challenge here is to get the most politically famous three Kennedy (John, Robert and Ted) elected as president at some point, noted you can only do this by democratic means, so no wacky scenario like American Juche is allowed, bonus if you can also get the following Kennedys to have successful political career:
Joseph Patrick Kennedy Jr (let say his WW2 death is butterflied away.)
John Kennedy Jr (same as above)
Caroline Kennedy (certainly can be more successful than she currently is)
Joseph Patrick Kennedy Jr (let say his WW2 death is butterflied away.)
John Kennedy Jr (same as above)
Caroline Kennedy (certainly can be more successful than she currently is)