ALBANY (AP) -- Primary voters are going to the polls in New York, where controversy over legalization of gay marriage last year and an unusual number of vacancies has upped the stakes.

The state Conservative Party has helped drive challenges to three upstate Republican senators who sided with Democratic Gov. Andrew Cuomo in the gay marriage vote: Mark Grisanti of Erie County, Stephen Saland of Poughkeepsie, and Roy McDonald of Saratoga County.

And there's an unusual number of contests without incumbents because more than 20 of 150 Assembly members and four of 62 senators have retired or resigned this term.

Turnout is expected to be low, making many of the races unpredictable.

The primary usually held on Tuesdays was moved to Thursday in observance of the Sept. 11 anniversary of the terrorist attacks.

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