President-elect Barack Obama Monday launched a hard sell for his near 800 billion dollar stimulus plan, warning the US economy would pay a dramatic price if the bill gets bogged down in Congress. Obama plunged into the political fray on his first day at work in Washington two weeks before his inauguration, after congressional power brokers on Sunday dashed hopes the rescue package could be ready as soon as he is sworn in. “The most important message today is that the situation is getting worse, we've got to act boldly, and we've got to act swiftly. We cannot delay,” Obama told reporters after meeting his economic advisErs. “This is not a Republican problem or a Democratic problem at this stage. It is an American problem and we're going to all have to chip in and do what the American people expect,” Obama said urging bipartisan cooperation. The president-elect's aides meanwhile revealed details of the massive scope of the stimulus package, his opening political gambit when he takes office on January 20 during the worst global economic crisis for more than 70 years. Obama will propose tax cuts totaling 300 billion dollars over two years, or around 40 percent of a package that could top 775 billion dollars, a transition source said on condition of anonymity. The president-elect has already previewed a multi-billion-dollar program of public works programs, including highway and bridge repairs, renovating school classrooms and aid to cash-strapped states. US citizens can expect immediate tax relief of around 500 dollars for individuals and 1,000 dollars for couples under the plan, and some businesses would be able to write off last year's losses against their tax return. The magnitude of the tax cut is being seen as a bid for Republican support for the stimulus program, especially in the Senate where the opposition party has enough seats to block legislation.