While administration officials cautioned on Thursday that no decisions have been made and that any debate in Congress could take years, Mr. Obama has directed his economic team and Treasury Department analysts to review options for closing loopholes and simplifying income taxes for corporations and individuals, though the study of the corporate tax system is farther along, officials said.

The objective is to rid the code of its complex buildup of deductions, credits and exemptions, thereby broadening the base of taxes collected and allowing for lower rates — much like a bipartisan majority on Mr. Obama’s debt-reduction commission recommended last week in its final blueprint for reducing the debt through 2020.

Doing so would offer not only an opportunity to begin confronting the growth in the national debt but also a way to address warnings by American business that corporate tax rates and the costs of complying with the tax code are cutting into their global competitiveness…

Yet proponents within the administration and among some outside advisers say that Mr. Obama, by putting tax reform atop the national agenda, could seize an opportunity to take the offensive in dealing with the newly empowered Republicans in Congress, repair his strained relations with business and embrace a potentially powerful theme heading into his re-election campaign.