Perhaps Senate Majority Leader Reid is being politically smart by passing a scaled down modest jobs bill. This $15 bill is surprisingly small based on a consensus that a bill near $100 billion could pass.
But I think Harry Reid is thinking, it is better to take numerous popular votes separately and get credit for them individually. If by election day, the Senate has passed 3 or 4 pieces of legislation that totals what they could do right now, but spreads it out over months, it will increase the imagery that Democrats are working on the number one issue: jobs.
There really isn't any policy difference to do 1 comprehensive bill or 3 or 4 smaller bills that add up to the same thing, but politically you can list them and get maximum credit.