WASHINGTON — House Republicans are rallying behind a modest budget pact that promises to bring a temporary halt to budget brinkmanship in Washington and ease automatic budget cuts that would otherwise slam the Pentagon and domestic agencies for a second straight year.

President Barack Obama and Senate Democrats also are praising the measure negotiated with House Budget Committee Chairman Paul Ryan, the Wisconsin Republican who has morphed, however briefly, from an uncompromising small-government stalwart into a dealmaker eager to claim a partial victory on the budget.

The deal Ryan negotiated with Senate Democratic counterpart Patty Murray would preserve the bulk of tough agency spending cuts the GOP won in a 2011 showdown with Obama, while reducing the chances of a rerun of the partial government shutdown.

It’s set for a vote Thursday.