"It's actually unprecedented for me to have that kind of lead at this point in the game," Matheson said Friday. "This is great news."
Swallow also interprets the survey results in his favor.
"I'm encouraged that it's not a greater deficit right now," the Republican nominee said.
Both camps expect the race to narrow sharply in the next month. About 13 percent of voters are still undecided.
"I expect it to tighten by Election Day," Matheson says. "I'm going to work hard every day. I expect to run stronger than I did last time."
Swallow says the incumbent has gotten a boost from his own television ads and those of his brother, Scott Matheson Jr., the Democratic gubernatorial candidate.
"We're in a holding pattern. But it could be a whole lot worse than this," Swallow said. "As soon as we get on TV, the numbers will move very quickly."
In the other congressional races, Utahns put Bishop, the first-term 1st District Republican, ahead of Steve Thompson, a Democratic Logan city councilman, 54 percent to 21 percent.
Cannon's seat also looks secure. The 3rd District Republican leads Democratic South Salt Lake City police Capt. Beau Babka 58 percent to 21 percent.
Minority party underdogs take heart, however, in the large chunk of undecided voters: 19 percent in Cannon's district and 23 percent in Bishop's 1st District.
"Voters don't know who I am," said Thompson, who complains of competing with the high-profile gubernatorial race for campaign donations. "I've struggled with funding and getting my message out. The coming televised debates will be critical for me."
Babka's campaign spokesman Jeff Bell notes that other surveys conducted by Utah pollster Dan Jones and Associates show Babka gaining, albeit slowly, on Cannon.
Joe Hunter, Cannon's chief of staff, blames the disparity on timing.
"The more recent the poll, the more dependable the numbers will be," said Hunter. "Voters are more focused now."
Democratic Senate candidate Paul Van Dam's campaign also notes a difference between polls. The Tribune poll showed Bennett leading Van Dam 62 percent to 19 percent with 17 percent of voters undecided, while a recent Deseret Morning News survey showed Van Dam at 23 percent.
Van Dam still holds out hope that radio and television advertising can turn his lopsided race.
"I've always known it's an uphill battle. Whatever's going to happen will happen in these last 30 days," Van Dam said. "The only poll I care about is that poll on Nov. 2."