ALBANY — President Obama’s job-approval rating among New York voters has plunged to its lowest level this year, 45 percent, according to a poll released yesterday.

The Siena College survey showed 55 percent of New Yorkers disapproved of Obama’s performance. As recently as May, just after the killing of terror mastermind Osama bin Laden, Obama scored a 53-47 positive rating.

The Siena survey found a huge racial divide in attitudes toward the nation’s first African-American president, with 78 percent of black voters, but just 35 percent of white voters, giving Obama a positive job-performance rating.