There's a VERY easy answer for this. It's called "recess appointment", and YES, it has been done with U.S. Supreme Court justices in the past. The most prominent was none other than Earl Warren, recess-appointed by Eisenhower.
I don't think Dubya has the inclination or guts to do this, of course.
Maybe he'll re-nominate Harriet Miers (HOWLS of laughter). She'll make it this time!
- John
Isn't a recess appointment only good for a limited time though?