To accommodate Senators’ religious views and scheduling conflicts, Senate Democrats hope to begin voting on the $789.5 billion economic stimulus bill as early 5 p.m. Friday, but may hold the vote open for several hours, Democratic sources said.

However, Republicans have not yet signed off on that plan, meaning the timing of the vote could still slip.

Because Sen. Sherrod Brown (D-Ohio) needs to attend a memorial service for his late mother, he may not be back for the beginning of the vote. Therefore, Democrats said they expect to keep the vote open for several hours to make sure Brown can provide them with a winning margin.

The Senate vote on the final version of the stimulus package will be close, given that Democrats need 60 votes to beat back procedural objections that are likely to be lodged by Republicans.

Further complicating matters, Sen. Edward Kennedy (D-Mass.), fighting brain cancer, is holed up in Florida and is not expected to return for the vote.

Only three Senate Republicans — Susan Collins (Maine), Arlen Specter (Pa.), and Olympia Snowe (Maine) — are expected to support the measure. So with Kennedy’s absence, Senate Majority Leader Harry Reid (D-Nev.) must have the votes of the remaining 57 members of the Democratic Conference in order to get to 60.