The opening salvo in the domestic issue was the Democrats' bid to spend an additional $35 billion on the State Children's Health Insurance Program, which President George Bush said is excessive and promised to veto.
The newspaper said Republicans are gearing up to challenge Democrats on spending issues, and will also look for taxation and illegal immigration confrontations.
Democrats, meanwhile, appear ready to bring such issues as hate crimes, taxation and universal health care back to the forefront, the Post said.
For some Republicans, the shift in focus is a relief.
"I think it is territory that tends to unite us more," said Senate Minority Whip Trent Lott, R-Miss. "Republicans tend to squabble, but when it's fiscal issues, when it's economic issues, we tend to come together."