With 119 of 120 counties reporting, the former Massachusetts governor had 66.77 percent of the vote in Kentucky, the state Board of Elections reported. U.S. Rep. Ron Paul of Texas, trailed with just under 13 percent, while former U.S. Sen. Rick Santorum of Pennsylvania had almost 9 percent and former U.S. House Speaker Newt Gingrich of Georgia had close to 6 percent, in a near tie with those who voted as "uncommitted."
Romney has an overwhelming lead in delegates to the Republican National Convention -- with 997, compared to 264 for his closest competitor, Santorum. CNN estimates Romney will lock up the nomination with the 1,144 needed to win it by the end of May.
President Barack Obama won the Democratic primary in Kentucky, but returns indicated soft support for the president. With most precincts reporting, 42.1 percent of Democratic voters in Kentucky opted for "uncommitted," while Obama got 57.9 percent of the vote.
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