Begich said he believes Miller will lose. When that happens, he said, it will send a message to the rest of the country that "Alaska knows Sarah Palin and knows what she's about, and we reject her type of politics."
Begich is backing fellow Democrat Scott McAdams. Murkowski is running as a write-in candidate after losing the August primary to Miller.
Begich, in an interview with The Associated Press on Saturday, called Miller a candidate selected by Palin for a "grudge match" between her and Murkowski. The two women have tangled politically over the last few years but as recently as the primary denied bad blood between them.
Their rhetoric, though, has become more caustic as the general election race has intensified. At a rally with Miller this week, Palin referred to Murkowski as an "out of touch liberal"; on Facebook, she said Murkowski is "flush with millions of dollars from vested corporate interests."
During a recent debate, Murkowski said she wouldn't support a presidential run by Palin at this time. She also has questioned whether Palin is putting Alaska's interests first.
Miller is among the "commonsense conservatives" Palin has backed this cycle. In a statement to the AP, Palin said Begich is "an outright liar if he claims I selected any candidate to run against Lisa.
"The independents and GOP voters in the primary election selected Joe Miller, and I support the independents' and GOP selection," she said. "I support Joe Miller."
Miller has welcomed Palin's backing but also has said he wants the race to be about issues, not endorsements. Miller's campaign expresses confidence in its chances of winning.
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