Even to the party faithful, an hourlong speech dense with terms like "costing the differential" is a tough sell. But Teresa Heinz Kerry came to Pueblo and sold it Friday. The wife of Democratic presidential candidate Sen. John Kerry was nearly an hour late when she finally showed for a town hall meeting at the Colorado State Fair Grounds, in the 4-H Pavilion just down the row from the sheep, swine and goat barn. By the time she got there, the crowd of more than 500 had gone through a God Bless America singalong and round-robin cheers of "John! Kerry!...