WASHINGTON (AP) _ An Associated Press polls finds that racial attitudes have not improved in the four years since the United States elected its first black president.

A slight majority of Americans now express prejudice toward blacks whether they recognize those feelings or not.

The AP survey finds that those views could cost President Barack Obama votes as he tries for re-election, though the effects are mitigated by some Americans’ more favorable views of blacks.

In all, 51 percent of Americans now express explicit anti-black attitudes, compared with 48 percent in a similar 2008 survey. When measured by an implicit racial attitudes test, the number of Americans with anti-black sentiments jumped to 56 percent, up from 49 percent in 2008.

In both tests, the share of Americans expressing pro-black attitudes fell.