Impeachment does not mean removal from office. It means being brought to "trial" for consideration of removal.
Bill Clinton was impeached. He was not removed from office.
The senate votes are not a limitation to impeachment, rather a limitation on the ability to remove from office, after impeachment.
A Senate trial is a necessary and mandatory result of a vote for Impeachment by the House. The two are mentioned in the same sentence in the Constitution. The Senate must act. They do not, however, have to convict, or even to hold a vote for conviction. When Articles of Impeachment are delivered to the Senate by the House, the Senate must convene as a trial to consider the Articles.
Why in the world would any body of government be foolish enough to adopt a resolution removing the Chief Executive if they had no possibility of carrying it out? It would be an empty gesture, and in this case one that Obama and his supporters desperately want as it is one of the few means available to them to rally his supporters. Impeachment in current circumstances is foolish, hopeless, and ill advised.
Unfortunately, impeachment without removal is almost a political "win" for the President. Certainly for a Democrat President, anyway. It is true that Bill Clinton was disbarred, and probably paid some civil fines, but I don't think he's hurting or caring too much about his legacy. The same would hold true for Obama.
Surely, our Founding Fathers had a President like Obama in mind when they gave instructions on how to legally impeach and remove. How do we both impeach and remove in today's partisan environment?