From what I remember of the Clinton fiasco (thanks Fred), the house has to vote to impeach. Clinton was impeached. But, then the Senate has to convict. Clinton and Johnson were both impeached but neither was convicted.
The total process presented
Impeachment Process for a US President Notice within the process laid out for the Senate:
1. The Senate, in open session, will vote on a verdict. A 2/3 vote of the Senate will result in a conviction.
2. The Senate will vote to remove the President from office.
Hope that helps clear things up.