WASHINGTON -LRB- CNN -RRB- -- Leading Republicans warned Sunday that the Obama administration 's $ 800 billion-plus economic stimulus effort will lead to what one called a `` financial disaster . '' The country will `` pay dearly '' if it executes the president 's stimulus plans , Sen. Richard Shelby says . `` Everybody on the street in America understands that , '' said Sen. Richard Shelby , the ranking Republican on the Senate Banking Committee . `` This is not the right road to go . We 'll pay dearly . '' Shelby , of Alabama , told CNN 's `` State of the Union '' that the package and efforts to shore up the struggling banking system will put the United States on `` a road to financial disaster . '' But Lawrence Summers , the head of the administration 's National Economic Council , said Republicans have lost their credibility on the issue . Watch Republicans criticize the stimulus bill '' `` Those who presided over the last eight years -- the eight years that brought us to the point where we inherit trillions of dollars of deficit , an economy that 's collapsing more rapidly than at any time in the last 50 years -- do n't seem to me in a strong position to lecture about the lessons of history , '' Summers told ABC 's `` This Week . '' President Barack Obama , his advisers and the Democratic leaders of Congress argue the roughly $ 830 billion measure will help pull the U.S. economy out of its current skid . Much of the package involves infrastructure spending , long-term energy projects and aid to cash-strapped state and local governments . The nonpartisan Congressional Budget Office reported last week that the measure is likely to create between 1.3 million and 3.9 million jobs by the end of 2010 , lowering a projected unemployment rate of 8.7 percent by up to 2.1 percentage points . But the CBO warned the long-term effect of that much government spending over the next decade could `` crowd out '' private investment , lowering long-term economic growth forecasts by 0.1 percent to 0.3 percent by 2019 . In a concession to Republicans , about a third of the bill involves tax cuts . But the measure is expected to have only minimal GOP support when it goes to a scheduled vote early this week . Watch South Carolina Gov. Mark Sanford warn of `` disastrous consequences '' The version of the bill that passed the House of Representatives had no Republican votes . `` We need to spend money on infrastructure and on other programs that will immediately put people to work . But this is not it , '' said Sen. John McCain , R-Arizona , last year 's GOP presidential nominee . Senators reached a tentative agreement Friday on a compromise bill largely negotiated by a handful of moderate Republicans whose votes are needed to prevent a filibuster . But McCain told CBS ' `` Face the Nation '' that the package should have been about half the size of the one now before senators , and should be balanced between tax cuts and spending . `` We 're going to amass the largest debt in the history of this country , by any measurement , and we 're going to ask our kids and grandkids to pay for it , '' he said . The stimulus bill includes about $ 45 billion in transportation spending , much of which can be spent on projects `` that can be implemented immediately , '' Transportation Secretary Ray LaHood told CNN . LaHood , a former Republican congressman from Illinois , said he would talk to his former colleagues on Capitol Hill `` and do all that I can to persuade them that this bill really will put people to work . '' He said he invited state transportation chiefs to Washington for a Wednesday meeting on how to create jobs using funding from the stimulus bill . `` There are n't going to be any boondoggles . This money will be spent correctly , by the book , with no shortcuts , '' LaHood said . The administration is also readying a second phase of the financial bailout program launched by the Bush administration last fall . Shelby said Obama and his advisers need to address the staggering problems in the U.S. banking system first . `` Until we straighten out our banking system , until there is trust in our banking system , until there 's investment there , this economy is going to continue to tank , '' he said . Shelby also has been critical of other efforts by the federal government to help the struggling economy , including legislation that would have provided a bailout to the auto industry . But Sen. Kent Conrad , the chairman of the Senate Budget Committee , told CBS the current recession -- which has already produced an unemployment rate of 7.6 percent -- is in danger of a deep downturn `` like we saw in the Great Depression . '' `` If there is a failure to give a significant boost to this economy , this crisis will only deepen and become far more serious , '' said Conrad , D-North Dakota .