By John Whitesides, Political Correspondent
In their hard-fought duel for the Democratic nomination, Obama won 12 states and Clinton took eight but that included the two biggest prizes of the night -- California and New York -- on the biggest day of U.S. presidential voting ahead of November's election.
McCain had had hoped to nail down the nomination with a big night and his nine wins included California and several big Northeastern states, but rival Mitt Romney took six states and Mike Huckabee won five.
The biggest prize of the night was California, which offers the country's biggest haul of delegates to party conventions that choose the parties' presidential candidates for the November 4 election to succeed President George W. Bush. U.S. media had predicted Clinton and McCain would win.
The Clinton and Obama camps said they expected the count of delegates for the night to be relatively even. "This is not going to be decided tonight," Democratic Party Chairman Howard Dean said on MSNBC.
About 44 percent of Republican voters preferred a candidate who shared their values, while one-quarter wanted a candidate with experience.
Economic worries -- plunging housing values, rising energy and food prices, jittery financial markets and new data showing a big contraction in the service sector -- eclipsed the Iraq war as voters' top concern in both parties, exit polls showed.
(For more about the U.S. political campaign, visit Reuters "Tales from the Trail: 2008" online at http://blogs.reuters.com/trail08/)
