ANCHORAGE, Alaska (AP) — Former Alaska Attorney General Dan Sullivan has won the Republican nomination for U.S. Senate in Alaska.

Sullivan had been the presumptive front-runner in a race featuring three prominent candidates. He had scored the backing of Washington, D.C., establishment Republicans and raised about four times as much as his nearest GOP rival, Mead Treadwell.

The race also featured tea party favorite Joe Miller, the 2010 GOP Senate nominee in a race won by Sen. Lisa Murkowski with a write-in campaign.

For months, Sullivan had been the focus of attacks by a super PAC supporting Democratic U.S. Sen. Mark Begich, creating an opening for his rivals. But his campaign, run by a professional staff of 14, grew increasingly confident of his chances as the primary neared.

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