Republican presidential front-runner Mitt Romney cruised to victory in the Nevada caucuses Saturday night, notching a second straight triumph over a field of rivals suddenly struggling to keep pace.

In victory, the former Massachusetts governor unleashed a sharp attack on President Barack Obama, whose economic policies he said have "made these tough times last longer."

In a state with the worst joblessness in the country, Romney added, "This week he's been trying to take a bow for 8.3 percent unemployment. Not so fast, Mr. President. This is the 36th straight month with unemployment above the red line your own administration drew."

The former Massachusetts governor held a double-digit lead over his nearest pursuer as the totals mounted in a state where fellow Mormons accounted for roughly a quarter of all caucus-goers.

Former House Speaker Newt Gingrich and Texas Rep. Ron Paul vied for a distant second. Former Pennsylvania Sen. Rick Santorum trailed the field.

Returns from 14 of 17 counties showed Romney with 42 percent support, Gingrich with 25 percent, Paul with 20 percent and Santorum with 13 percent.

Yet to report its results was Clark County, which includes Las Vegas and often accounts for half or more of the votes in a statewide election.

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