Minimum wage hike blocked by Senate GOP. Obama fires back.

U.S. President Barack Obama blasted Senate Republicans on Wednesday just hours after they blocked one of his top legislative priorities, a  federal minimum wage hike that would be the first since 2009.

"They (Republicans) prevented a raise for 28 million hard-working Americans. They said no to helping millions work their way out of poverty," Obama said at the White House, backed up by low-wage workers.

On a nearly party-line vote of 54-42, Obama's Democrats fell short of the needed 60 Senate votes to end a procedural roadblock against a White House-backed bill.

The legislation would raise the minimum hourly wage from its current $7.25 to $10.10 per hour during the next three years, and then index for inflation in the future.

Just one Republican, Senator Bob Corker of Tennessee, joined Democrats in voting to advance the measure.

Senate Majority Leader, Democrat Harry Reid switched his vote from yes to no to reserve his right to bring up the bill again.

With polls showing that more 60 percent of Americans support raising the minimum wage, Democrats intend to hammer away at the issue in an effort to rally their liberal base in advance of the November congressional elections.

"Change is happening, whether Republicans like it or not," Obama said. "And so my message to the American people is this: Do not get discouraged by a vote like the one we saw this morning. Get fired up, get organized, make your voices heard."

The non-partisan Congressional Budget Office estimated that the bill would raise the wages of 16.5 million Americans and lift 900,000 of them out of poverty.

But it also estimated the bill could cost up to 1 million Americans their jobs because businesses may simply be unable to afford to pay them.

Republicans on Monday cited a Bloomberg Poll in which 57 percent of respondents said it was an "unacceptable" trade-off if the bill raised the incomes of 16.5 million Americans while eliminating 500,000 jobs.

Democrats argue an increase in the minimum wage would boost the economy overall by getting more money into it.

"Millions of American workers will be watching how United States senators vote today," Senate Democratic Leader Harry Reid said before the vote. "They'll be observing to see if we ensure all full-time workers in this country receive livable wages."

Senate Republican Leader Mitch McConnell mocked Democrats, saying: "They don't even pretend to be serious about jobs anymore."

The Democrats' "true focus" was on "making the far left happy - not helping the middle class," McConnell said. (Additional reporting by Steve Holland; Editing by Jim Loney and Gunna Dickson)