WASHINGTON — Bucking the Obama administration, House Republicans on Wednesday defeated a bill to postpone the upcoming transition from analog to digital television broadcasting to June 12 — leaving an estimated 6.5 million U.S. households unprepared for the currently scheduled Feb. 17 switchover.

But the battle over a delay might not be over, with some predicting the House will take up the measure again next week.

Wednesday's 258-168 House vote failed to clear the two-thirds threshold needed for passage in a victory for GOP members, who warn that postponing the transition by four months would confuse consumers.

House Republicans say a delay also would burden wireless companies and public safety agencies waiting for the spectrum that will be freed up by the switch, and create added costs for television stations that would have to continue broadcasting both analog and digital signals for four more months.

The defeat is a setback for President Barack Obama and Democrats on Capitol Hill, who maintain the Bush administration bungled efforts to ensure that all consumers — particularly poor, rural and low-income Americans — will be ready for next month's analog shut-off.

Wednesday's House vote came two days after the Senate unanimously passed the bill. The Senate is expected to vote on the bill again to incorporate minor changes in the House version so it can go directly to the White House for President Obama's signature if it clears the House next week.