Bill Clinton and Andrew Johnson spring to mind as the only two impeached presidents. President Obama sucks too.
Johnson-a Democrat who ran with Lincoln on the National Union ticket-had the problem of pissing off the extremists in both parties. Johnson wanted to follow Lincoln’s vision; some hard-core re-construction folks in the Republican party didn’t, and from there things went downhill fast.
Oddly enough, although he was nearly impeached by the senate, when Johnson returned to the Seante in 1874 he was greatly welcomed back.