Louisiana may have been Rick Santorum's last hurrah, except for his home state of Pennsylvania.  The April primary looks very good for Mitt Romney.  And we are now into the "winner take all" stage of delegate selection.  Wisconsin, Maryland, and D.C. are April 3.  Three weeks later, primaries are held in New York, Connecticutt, Rhode Island, Delaware, and Pennsylvania.  The polls and pundits all suggest that Romney will win all but Pennsylvania, and that he has a good chance of defeating Santorum there and sweeping the table.  In the process, he will collect a bucket load of delegates, although technically not enough to clinch the nomination.  Santorum would be wise to recognize the obvious and concede now, rather than running up a huge campaign debt.