Two senators who played a leading role in shaping the $827 billion bill now before lawmakers say it's the best that could be achieved under difficult circumstances and must be passed.

The pair -- Susan Collins of Maine and Ben Nelson of Nebraska -- said Monday morning they hope that differences between their version and the $827 billion House bill can be worked out in conference.

Collins is a Republican and Nelson is a Democrat. They spoke on the eve of a critical floor vote on the bill. The measure has attracted the support of Collins and two other Republicans in what supporters believe is enough strength to get it past a key procedural vote later Monday.

Appearing on NBC's "Today" show, Collins conceded "the bill is not perfect." But she said the country is facing a crisis and doesn't need "a partisan divide."