Mitt Romney had a good night last night. Very good:
Romney beat Rick Santorum by just under 12 percent in the popular vote which is pretty good, even though he fell below 50 percent. But Romney really cleaned up in the delegate count, taking 43 delegates to Santorum's 10. Fifty-four of Illinois' 69 delegates that were available last night, so with one delegate still unallocated, Romney converted his 46.7 percent popular vote win into a 79.6 percent delegate win. That's Mitt Romney's kind of math, and it's perfect for the Republican Party: Winners win bigger, and losers lose harder.
The net result of last night's delegate allocation is that Mitt Romney has not only moved 43 delegates closer to being the nominee, but he now needs just 45.9 percent of the remaining delegates to be the nominee (based on AP's delegate count). That figure had been trending in the wrong direction for him, but he's gotten things back on track over the last two contests.
The only sliver of hope for Rick Santorum is that there are still 104 unallocated delegates from states that have already voted or held caucuses. Many of those delegates are either super delegates or won't be selected until state conventions that won't take place until the summer. If you assume none of those delegates will be allocated before voting ends in June (and that's a big if), then Romney still must win 50 percent of the delegates available in the remaining states.
As it just so happens, however, that's exactly the pace Romney has been on. So if he can continue to win at the clip that he's won so far, he wouldn't need to get any additional support from those 104 unallocated delegates. If Santorum is unable to reverse that trend in next Tuesday's contests, it'll be hard to see any plausible scenario for Santorum to deny Romney the magic number, let alone win the nomination.