A string of recent polls through this week had shown all good news for Dan Sullivan, the Republican challenger for the U.S. Senate seat held by incumbent Democrat Mark Begich.

That changed Friday, with a poll released by Begich's Democratic allies in the morning showing the race in a dead heat -- and a second survey released by a Republican pollster in the afternoon showing Begich leading Sullivan 49 percent to 39 percent.

The second poll was conducted by a firm owned by Anchorage Republican pollster and consultant Marc Hellenthal, who was hired by several individuals including lobbyist Sam Kito Jr.

Kito, who's not registered with a party and whose clients include the Alaska Cruise Association, the Alaska Travel Industry Association and GCI, said he had commissioned the poll along with three or four other people whom he declined to name -- but added that none of them is affiliated with candidates.

If anything, the results show the unpredictability of polling in Alaska, a state that's notorious among national pundits for being difficult to survey.

Hellenthal, in an interview, attributed part of the divergence in his results to the fact that the vast majority of his respondents had been reached on mobile phones. Landlines, he added, have had a very poor response rate; he noted that one of his firm's recent polls resulted in 76 survey completions for about 1,100 calls to landlines.

One answering machine reached by Hellenthal's callers, he said, actually had a recording saying: "If this is a survey, hang up. We are not interested."