Election not Coronation

We all know the President of the United States is restricted to 2 terms in office. Should that not apply to Senators? This is the reigning top 4.

1 Robert Byrd (D-WV) since January 3, 1959 48 years

this one is truly amazing

2 Ted Kennedy (D-MA) since November 7, 1962 44 years

3 Daniel Inouye (D-HI) since January 3, 1963 43 years

4 Ted Stevens (R-AK) since December 24, 1968 38 years

They don't even campaign anymore. Their reign is taken for granted.

Election not Coronation