SACRAMENTO . (AP) — A former state assemblyman is expected to win a special election to a GOP-leaning Senate district that covers a wide swath of rural Northern California.

Republican Jim Nielsen of Gerber nearly won the 4th Senate District seat outright during November's special primary but fell just shy of a simple majority. He split votes with another GOP candidate.

Republicans have a 12-point registration advantage in the district, which includes all or parts of 12 counties stretching from areas north of Sacramento to the Oregon border.

The seat opened last year when Republican Doug La Malfa, who had two years remaining in his term, successfully pursued a congressional seat.

Tuesday's runoff pits Nielsen against Democrat Mickey Harrington of Magalia.

The outcome will not affect Democrats' supermajority in the Senate.