Elections if Kennedy Lives

[True Federalist (진정한 연방 주의자)]

I think a weaker Civil Rights Act passes, no stronger than the one introduced in 1963, which means the EEOC is only an investigatory body with no employment discrimination provisions as in OTL's Title VII.  As Kennedy was considering, he dumps Johnson and replaces him with Gov. Sanford of North Carolina.  Needless to say LBJ is P.O.ed. and doesn't work very hard for the Democrats that fall.  Not only does Texas go Republican in the Presidential Race, but George H. W. Bush wins his Senate race against Ralph Yarborough,  However Kennedy/Sanford still have a landslide against Goldwater/Miller, it's just not as strong.

1964

Kennedy (D-Mass.) / Sanford (D-N.C.) 421
Goldwater (R-Ariz.) / Miller (D-N.Y) 117

Besides, Texas, other Republican gains/holds in the Senate that didn't happen in real life would include Nevada, New Mexico, New York, Ohio, Oklahoma, and the special election in Tennessee, tho Gore Sr. would be reelected in the regular Tennessee election.  So instead of a two seat gain, the Democrats would lose four to have only 62 Senate seats, five short of being able to override a Republican filibuster. (The Senate still had the two-thirds rule in those days.)

In the House, the Republicans gain or hold the following 31 seats, leaving the Dems with only a 264-171 majority:
Alaska - At Large
Arizona - 3rd
California - 22nd
Colorado - 2nd, 3rd
Connecticut - 4th
Idaho - 1st
Indiana - 11th
Iowa - 1st
Michigan - 2nd
Minnesota - 6th
Nebraska - 1st
New Hampshire - 1st
New Jersey - 2nd, 3rd, 9th, 12th
New Mexico - one of the two At-Large seats
New York - 3rd, 27th, 34th
Ohio - 1st, 3rd, At-Large
Pennsylvania - 19th
Tennessee - 9th
Texas - 5th
Virginia - 3rd
Wisconsin - 1st, 6th
Wyoming - At Large

North Carolina's 4th would almost have been a Republican gain, but the presence of Sanford on the ticket helps the Dems enough in North Carolina for Cooley to retain his seat and the Chairmanship of the Agriculture Committee.

The 1968 and later elections depend hugely upon how Kennedy approaches Vietnam.  It's doubtful Kennedy would have gotten us as involved in Vietnam as Johnson did, but that still leaves a lot of wiggle room.

[True Federalist (진정한 연방 주의자)]

I think it's very unlikely Kennedy would run against Goldwater in 1964. I think the Republicans would have either nominated Nixon for a rematch or Nelson Rockefeller because those two in my opinion probably would be the only ones with a chance to make Kennedy a one term president.

There's no way Nixon runs in 1964.  After his losses in 1960 and 1962, he needed to recharge his political strength. It wasn't just Democratic strength that caused him to forgo a run.  While Rockefeller no doubt would have run as he did, the same factors that caused him to lose to Goldwater, his divorce and quick remarriage to a much younger woman would cause problems.  Goldwater won the nomination because he was the sole conservative candidate facing multiple moderate Republicans who divided the field (Lodge, Rockefeller, and Scranton).  Much as the Republicans in 2012 had problems selecting an anti-Romney, in 1964 they had problems selecting an anti-Goldwater.  There's nothing in your point of divergence that alters any of that.

[True Federalist (진정한 연방 주의자)]

If Nixon wins in '62 he won't be running for President in '64 unless he is brought forth as a compromise candidate at the convention.  That's the only realistic chance for Nixon to be making a second attempt so soon.  Also I fail to see how a Nixon win in '62 could be the cause of Kennedy not being assassinated unless one argues that happened because Nixon was in Dallas that day.