Bipartisan legislation to soften across-the-board spending cuts gained ground among Senate Republicans on Monday and Democrats expressed optimism it would gain the 60 votes needed to pass by week’s end.

Republican Sens. Orrin Hatch of Utah and Georgians Johnny Isakson and Saxby Chambliss of Georgia announced they would vote to send the measure over a critical hurdle in a test vote set for Tuesday, bringing the number of GOP lawmakers to seven. Sen. John Hoeven of North Dakota said he was inclined to join them.

The announcements more than offset an announcement from Sen. Richard Burr, R-N.C., who reversed course and said he would vote to block the bill.

Given the uncertainty, Democrats, who control 55 seats, were under pressure to avoid defections on the vote.

The measure at the center of the maneuvering would restore about $63 billion in across-the-board cuts scheduled to take effect in the current budget year and the next one.

To offset the spending increases, the White House-backed legislation calls for $85 billion in budget savings over the next decade, extending existing cuts to Medicare providers, for example, raising a security fee on airline tickets and requiring federal civilian employees to pay a greater share of their own pensions.

Another element, to save about $6.3 billion over a decade by holding down increases in military retirement pay, has drawn opposition from veterans groups and Republican Sens. Kelly Ayotte of New Hampshire, Roger Wicker of Mississippi and Lindsey Graham of South Carolina.

Under the provision, annual cost of living increases would be held slightly under the rate of inflation for military retirees under the age of 62. In a statement issued last week, the three senators said a 42-year-old sergeant first class retiring after 20 years would lose about $72,000 in income over his lifetime.

One member of the Democratic leadership, Sen. Chuck Schumer, said of the bill, “It is a pretty safe bet it’s going to pass. … I think Mitch McConnell (the Kentuckian who is the Senate GOP leader), the Republican leadership knows they can’t let it go down.” While he spoke on MSNBC before Burr’s announcement, an aide said the switch did not diminish Schumer’s optimism.

The bill cleared the House last week on a lopsided vote of 332-94, with Speaker John Boehner and the rest of the GOP leadership working hard to build support for it.

The measure became something of a prize in a long-running struggle between tea party-aligned conservative groups who oppose it and establishment Republicans eager to demonstrate an ability to govern smoothly and to erase the taint on their party from October’s partial government shutdown.

Across the Capitol, where Senate Democrats are in the majority, the entire GOP leadership has either announced its opposition to the measure or is expected to.

At the same time, there is no evidence of a concerted effort by McConnell or his second-in-command, Sen. John Cornyn of Texas, to defeat the bill and open up the possibility of more politically damaging budget brinkmanship in January.

Additionally, both men have drawn tea party-backed challengers in next year’s re-election campaigns, and McConnell, in particular, has championed the spending levels that would be raised.

Cornyn’s position was unclear for part of the day, with his Senate office saying he had concerns about the bill and his campaign website stating his unequivocal opposition. The website was changed a short while later to remove mention of opposition.

In announcing his switch, Burr cited a provision in the measure that Alabama Sen. Jeff Sessions, the senior Republican on the Budget Committee, said would “remove a key protection against future tax-and-spend legislation.”

Sens. John McCain and Jeff Flake of Arizona; Susan Collins of Maine and Ron Johnson of Wisconsin had previously announced plans to support the measure on the test vote.

Hatch said it was a “commendable compromise that reduces our debt over the long term, prevents another government shutdown, and stops the budget battles that have rocked America with economic uncertainty and political pessimism.”

Hoeven said he was inclined to support the bill after talking with Rep. Paul Ryan of Wisconsin, the chief Republican architect, among others. While expressing concern about the military retirement provision, he noted it does not take effect for two years and said he will seek changes in the meantime.

(AP)