Pennsylvania was a should-win state for Hillary Clinton, and she went out and did just that yesterday, in commanding fashion. Clinton defeated Barack Obama by 10 points (her same margin of victory in neighboring Ohio on March 4) and more than 200,000 votes. Clinton also won 60 of the state's 67 counties.

If Obama was to be successful in at least holding Clinton to a single-digit victory, he needed to net a large number of votes in the greater Philadelphia area (including Philly and the eight surrounding counties). However, Obama netted just 90,000 votes, not nearly enough to stave off Clinton's strong support in the western part of the state. In the Pittsburgh area alone (Allegheny County and the five surrounding counties), Clinton netted 100,000 votes. In Northeastern Pennsylvania, Scranton's Lackawanna County and neighboring Luzerne County gave Clinton 60,000 net votes.

Obama's support in Philadelphia was good -- 54 percent of the city's registered Democratic voters went to the polls and 65 percent of them voted for Obama. However, had he increased his winning percentage to 70 percent there, it would have given him 20,000 more votes and held Clinton to an 8-point victory statewide.

Of course, this didn't happen. And Clinton's winning margins in the Pittsburgh and Scranton areas, and parts of suburban Philadelphia, allowed her to walk away with the double-digit victory most thought she needed to continue the race through at least the North Carolina and Indiana primaries on May 6.