Obama widens coalition in Potomac primaries

Barack Obama made it another clean sweep tonight, this time in the so-called Potomac primaries in Maryland, Virginia and Washington D.C.

The victories - when the votes are counted - will be by roughly 25 to 30 points in Virginia and Maryland, much the same as Obama's wins in the contests this past weekend. The victory in D.C. will be closer to 50 points.

But to really absorb the magnitude of Obama's wins, you have to look at the exit polls, where you will find that certain voting blocks that have been going for Hillary Clinton in previous contests may be starting to be won over by Obama.

In Virginia, Obama got 50% of the white vote to 49% for Clinton. Some 56% of white men went for Obama.

In the 60-plus age group, Obama won 54% to 46%.

Obama also won among all income groups, and won by 20 to 30 points in the various groups at $50,000 or below - groups (like those mentioned above) that Clinton has won in previous races.

Obama also got 60% of those who maxed out their education with a high school diploma, another group that Clinton has attracted until now.

Some 70% of those who identified themselves as Republicans in Virginia voted for Obama. Among independents, 66% went for Obama.

Obama also won among Catholics 50% to 48%, a first-time win for him in that category as well.

Sparing the details, Obama made similar inroads among the same groups of voters in Maryland , though Clinton won the overall white vote 51% to 46%.

Perhaps the most disconcerting numbers for Clinton are the gains made by Obama among lower-educated and lower-income voters. These groups are going to be key in upcoming races in Wisconsin, Texas and Ohio.

The same is true for the gain in Catholic voters, a key constituency in cities like Cleveland and all of northern Ohio, as well as Milwaukee and other ethnic enclaves in Wisconsin.

The bad news for Clinton is the widening delegate count for Obama, but the worse news for the New York senator is Obama's widening coalition.

On the Republican side, John McCain was the winner in all three races. He's projected by the networks to have won big in Maryland and D.C.

But Mike Huckabee continues be that annoying flea buzzing around his face, getting a little over 40% of the vote in Virginia.