"Business leaders that I talk to, many of whom supported him, would never support his re-election and in fact will work against him, myself included," Zwick said.
If Lee is worried, he isn't showing it. The freshman senator strongly defended the strategy of demanding that Democrats agree to defund the new health-care law, often called "Obamacare" by critics and others, or see the government shut down.
"This fight was worth fighting," said Lee, 42, a lawyer whose father served as U.S. solicitor general during the Reagan administration. "The country wasn't built by fighting only those battles where victory was certain."
This battle has taken a toll on his popularity, however. A Brigham Young University survey conducted during the shutdown found that 57 percent of Utahans wanted Lee to be more willing to compromise. The senator's approval rating dropped to 40 percent — down from 50 percent in June — with 51 percent disapproving.
At the same time, the online poll found, the vast majority of Utah residents identifying with the tea party still backed Lee.
Lee waved off the findings. "The only number I worry about is how many people are being hurt by Obamacare," he said.
But Lee acknowledged that voters disapproved of the shutdown — especially in Utah, where the federal government is the largest employer. Shuttered national parks hurt the tourism industry and thousands of workers at military installations were furloughed.
"I understand that people in Utah — and people in America, for that matter — don't like fighting in Washington," Lee said. "But if we don't have these fights, nothing changes."
Lee came to office as part of the 2010 tea party wave, benefiting from Utah's unique nomination system in which delegates chosen at neighborhood caucuses pick the party's candidates at a state convention rather than in a primary.