WASHINGTON -- President-elect Barack Obama and congressional Democrats are crafting a plan to offer about $300 billion of tax cuts to individuals and businesses, a move aimed at attracting Republican support for an economic-stimulus package and prodding companies to create jobs.

The size of the proposed tax cuts -- which would account for about 40% of a stimulus package that could reach $775 billion over two years -- is greater than many on both sides of the aisle in Congress had anticipated. It may make it easier to win over...