A quick tidbit.

Data on ad-buying compiled by CMAG and reported by the Cook Political Report demonstrates one reason that the Republican race may be tightening.* Put simply, the density of ads going after Donald Trump has increased dramatically since voting began at the beginning of February.

The first week of that month, only 9 percent of the ads that ran on broadcast and national cable networks were ones that targeted Donald Trump. Over the first week of this month? Nearly half.

For months, most of the punches being thrown were at and/or from people who are now out of the race. There's a reason that campaigns use negative ads: They tend to work. This data from CMAG suggests that Trump's opponents have finally figured that out.

After spotting Trump a few hundred delegates.

* Didn't know the race appeared to be tightening? Read The Washington Post!