“I think he didn’t realize the groups, the number of people who feel like the Finance Committee package is by far the right thing to do,” Baucus said at a Monday news conference when asked why his assessment differed from Reid’s.

The influential senior’s lobby, AARP, and groups representing homebuilders, union employees and war veterans spent the weekend calling on wayward senators to support the Finance Committee measure.

The Senate on Monday will vote to begin debate on the House’s economic stimulus bill, but final passage on the upper chamber’s version is unlikely until mid-week.

By loading up the bill with extra provisions, Republicans say Democrats are unnecessarily holding up a bill needed immediately to jump-start the slumping economy. The White House has called on the Senate to pass the House bill so President Bush can immediately sign it into law. GOP leaders are trying to limit defections in advance of this week’s critical votes.

The Finance Committee bill is much broader than the economic stimulus package approved by the House, which would provide $600-per-person rebate checks to most taxpayers covered under the eligibility requirements. But the Finance Committee package covers low-income seniors and recipients of federal disability payments, handing out $500 per person. The Finance bill also would extend unemployment benefits for three more months, provide businesses with generous tax write-offs for losses and extend $5.5 billion worth of tax credits for renewable energy use.

The Finance bill would cost taxpayers about $155 billion over the next decade, far greater than the House-passed bill, according to congressional estimates.