WASHINGTON (AP) — Senate Republicans derailed a Democratic drive Wednesday to raise the federal minimum wage, blocking a cornerstone of President Barack Obama's economic plans and ensuring the issue will be a major feature of this fall's congressional elections.

Facing the threat of a GOP Senate takeover, Democrats have forced votes on a procession of bills designed to amplify their message of economic fairness. Republican senators accused Democrats of playing politics by pushing a minimum wage measure designed to lure voters but too expensive for employers and sure to result in lost jobs and higher inflation.

"This is about trying to make this side of the aisle look bad and hard-hearted, and to try to rescue this midterm election," said No. 2 Senate GOP leader John Cornyn of Texas.

The legislation by Sen. Tom Harkin of Iowa would increase the $7.25 hourly minimum wage for American workers in three steps until it reached $10.10 after 30 months, with annual increases for inflation afterward. The minimum has been at $7.25 since 2009, with 3.3 million Americans — including disproportionate numbers of women and younger people — earning that figure or less last year.

"We saw this morning a majority of senators saying yes, but almost every Republican saying no to giving America a raise," Obama said in pointedly political remarks at a White House event with low-wage workers. "And then if they keep putting politics ahead of working Americans, you can put them out of office."

All but daring Republicans to vote against the measure, Harkin said before the vote, "Who's going to vote to give these people a fair shot at the American dream? And who's going to vote against it?"

The answer came moments later when senators voted 54-42 to continue debating the legislation — six votes short of the 60 needed to keep the measure moving forward. Every voting Republican but one — Bob Corker of Tennessee — voted no.