Less than 600 votes separated them last time, but with eight weeks to go in their rematch, Democratic Rep. Tim Bishop has seized a 13-point lead over Republican Randy Altschuler, according to a new poll released Thursday.

According to Siena College, Bishop (D-Southampton) leads Altschuler, a St. James businessman, 52 percent to 39 percent, among 624 Suffolk County voters surveyed from Sept. 5 to 10. Notably, Bishop led among independent voters, 49 percent to 41 percent.

The poll has a margin of error of plus or minus 3.9 percentage points.

Siena said that voters saw Bishop as better representing them on most issues, including taxes, jobs and the war in Afghanistan.

The two candidates have recently unleashed critical television ads against each other.

In 2010, Bishop barely edged Altschuler in a race that wasn't declared over until 38 days after Election Day -- making it the last outstanding congressional race that year.