Ron Paul, during the mid 1970s to the early 1980s, was first elected in a Democrat district in a special election. Then lost in the general. He then came back and won in the next general. He then increased his majorities to the point that he eventually ran unopposed.
During the 1990s to the today, he has done approximately the same thing in a new district that originally leaned Democrat, except that the Democrats thought they could mount a challenge to him last year and actually ran a candidate who got his head handed to him.
With regard to Chuck Hagel, he runs up enormous victories in Nebraska.
His last blowout victory came on the heels of his Iraq War vote (he voted for it).
He hasn't faced the voters since stabbing the President (and the troops he sent to fight) in the back became his favorite pastime.
Paul lost his first election in 74
He won and lost in 76
Won in 78, 80, and 82.
He lost in 84
Failed as Libertarian Party presidential candidate in 88 with 0.47% of the popular vote
Won Congressional seat in 1998 which he still holds....despite his loud calls for term limits LOL