An interesting, brief, to-the-point post from Dan Shaviro:

...in watching discussion of the Republican race, I was struck (though I've noticed this for a while) about how "fiscal conservative" now means someone who favors huge budget deficits. More specifically, a "fiscal conservative" favors huge and unending tax cuts while having no obligation whatsoever to address the outlay side other than through very vague and general rhetoric. Thus requiring huge and ever-growing deficits as a matter of simple arithmetic.

What Dan doesn't say is that this is a natural outgrowth of the position taken by most fiscal conservatives these days (but increasingly disputed with facts) that all tax cuts pay for themselves so that there is no reason to find offsets.