Mitt Romney has won the New Mexico Republican presidential primary, adding to a delegate total that already exceeds the number needed to win the nomination. Romney also won primaries today in New Jersey and South Dakota. Two more states, Montana and California, also are having primaries. A total of 264 delegates are at stake in Tuesday's contests, and Romney has a chance to win them all. Not that it matters much: Romney has 1,266 delegates. He needs 1,144 to win the nomination. After today, only one Republican presidential primary remains, in Utah on June 26.