Arizona's two most conservative members of Congress stood on lonely ground Friday, voting against providing back pay for federal workers going unpaid during the ongoing government shutdown.

It was a position only seven members of the 435-member House of Representatives took and happened on the day an estimated 800,000 workers missed their first paycheck since the 21-day-old shutdown began on Dec. 22.

On Thursday, the Senate unanimously passed a measure to provide back pay for the furloughed and unpaid workers whenever the shutdown ends and would provide similar assurances to workers in any future government closures.

Reps. Andy Biggs and Paul Gosar, both of whom are Arizona Republicans, voted against it in the House, which passed it 411-7 with 16 members not voting. President Donald Trump indicated earlier this week he would sign the bill, spurring its passage in the Senate.

Daniel Stefanski, a spokesman for Biggs, said the promise of future back pay was a deal-breaker for him.

"While Congressman Biggs empathizes with people who are not getting paid during this government shutdown — and has even asked that his pay be withheld for the duration of the shutdown — he voted no on (the bill) because it permanently extends back pay to government workers for all potential shutdowns, anticipating and incentivizing future shutdowns," Stefanski said.

"He would have supported a bill to extend back pay to the workers affected by the current shutdown. In addition, Congressman Biggs has introduced a bill to resume pay immediately for select federal security officials and employees, including Border Patrol, (Immigration and Customs Enforcement and Transportation Security Administration) agents."

Gosar did not respond to The Arizona Republic's requests for comment.

The back-pay promise "is scarce consolation for these federal workers who are desperate to make ends meet right now," said House Speaker Nancy Pelosi, D-Calif. "Their paychecks are going to be late, but they must pay their bills on time and in full.

"The impact of a missed paycheck is catastrophic in the lives of these Americans when they can't pay their mortgage, their rent, their utilities bill, their car payments, children's tuition payments on time. The list goes on. It affects their credit rating."

Pelosi noted that the pay issue has an outsize impact on veterans who work in the government.

Biggs and Gosar occupy two of the safer GOP districts in Arizona.

Biggs won a second term in Arizona's southeast Valley-based 5th Congressional District in November by 19 percentage points.

Gosar won a fifth term in Congress from the 4th District that spans northwestern Arizona by 38 percentage points.

The other five Republican House members who voted against back pay were: Justin Amash of Michigan, Glen Grothman of Wisconsin, Thomas Massie of Kentucky, Chip Roy of Texas and Ted Yoho of Florida.

Roy, who is among the members of Congress forgoing pay during the shutdown, explained his vote in a tweet.

"There is zero question that we should pay federal workers," Roy said in a statement. "I do not, however, support putting federal spending on autopilot indefinitely or authorizing future pay irrespective of the circumstances. I would gladly have voted to pay federal employees at the end of the current lapse, but we should do so methodically and always ensure we are managing the budget wisely."

The shutdown, which revolves around Trump's insistence on $5 billion for a border wall, will become the longest in U.S. history on Saturday, and leaders from both parties have said no end to the impasse is in sight.

It is considered a partial shutdown because much of the federal government already has a spending plan approved for the current budget year.

For those who do not, about half the affected workers are on furlough, unable to work and now going without pay. The other half are still working jobs deemed essential, but are not getting paid for their labor.

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