New York Rep. Timothy H. Bishop, a four-term Democrat from eastern Long Island, has a well-funded challenger on his hands. Randy Altschuler, an entrepreneur touted by Republican officials as a promising challenger, reported $659,000 in campaign receipts for the third quarter, including $450,000 from his own pockets.

Altschuler — who is hoping to put the GOP back into competition in the 1st District after three comfortable re-election wins by Bishop — ended the quarter with $538,000 in remaining cash on hand. The challenger got a reporting jump on Bishop, who like all other 2010 candidates must file his report electronically with the Federal Election Commission by the deadline of midnight tonight.

The Suffolk County Democratic Party quickly responded with a release noting that just one of Altschuler’s contributions, for $2,300, came from a district resident. Many of his donors are based in New York City.

Bishop had just more than $300,000 in receipts and $516,000 in cash on hand as of June 30, the end of the second quarter reporting period.