What will an Obama administration and a Congress with increased Democratic majorities do? That's a relevant question, given the Democrats' leads in the polls. And it's a little hard to answer, given the financial crisis that has been raging and the recession that seems to be ahead.

One thing they will certainly do is raise taxes on high earners. The Bush tax cuts are scheduled to expire in 2010, and congressional Democrats will gleefully allow the top rates to rise. Left-leaning Democrats, like Barack Obama himself, want to "spread the wealth around," as the candidate told Joe the Plumber in October. Blue Dog Democrats want to reduce the budget deficit and will welcome the additional revenue that the Congressional Budget Office's static-analysis models will promise. Raising taxes when the economy is weakening is not the medicine prescribed by Keynesian economics, and it is probably not what Obama's economic advisers would prescribe if they were starting from scratch today. It is what Herbert Hoover and Congress did in the early 1930s, and it helped to produce the Great Depression. But it is baked into the pie.

So is a slide toward trade protectionism. The breakdown of the Doha Round and House Speaker Nancy Pelosi's refusal to bring the Colombia Free Trade Agreement to a vote mean that both multilateral and bilateral trade liberalism channels are clogged. Obama may or may not try to renegotiate NAFTA, as both Canada and Mexico have center-right governments satisfied with current arrangements. But the trend will be toward less free trade.

The prospects are cloudier for two other issues on which Obama has made big promises. Much of the next Congress's time and psychic energy will be taken up with refashioning financial regulation -- a subject of considerable difficulty. And the looming recession will make it politically risky for Democrats to push big spending programs.

This means that Congress in the next two years may not pass Obama's national health insurance plan. The weakening economy and the enraged reaction earlier this year to $4-a-gallon gasoline also make it less likely that Congress will pass carbon reduction legislation -- certainly not a carbon tax and probably not a cap-and-trade system.

Regional impact. In any case, health insurance and carbon reduction will be heavily lobbied, despite all the denunciations of lobbyists issued by Obama (and John McCain). Any one-size-fits-all healthcare bill affects various regions differently, because we have many healthcare delivery and finance systems across the country. The same goes for carbon reduction legislation, as the economies of some regions depend more heavily on coal than do others; it may be hard to convince voters there that we have to impose burdens on them today to achieve promised benefits in 2050. These disparities cut across party lines and helped defeat the Clinton healthcare proposals in 1994. They will probably come into play again if far-ranging bills are pressed forward.

Two issues pushed by Democrats in this Congress have no budgetary costs. One is the "fairness doctrine," which is intended to shut down talk radio, the one communications medium in which conservative voices are dominant. The other is the so-called card check bill, which requires employers to bargain with unions when

their organizers secure signatures on cards from a majority of employees; secret-ballot unionization elections, required now, would be a thing of the past. The aim is to vastly increase union membership, pumping money into a Democratic pressure group.

What might happen in the unlikely event McCain is elected and faces a Democratic Congress? Presumably he would try to hold tax rates down, but to do so he might have to embrace the kind of bipartisan tax reform enacted in 1986, with low rates and fewer preferences. Democrats might be willing to bargain if they could get rid of the alternative minimum tax, which threatens their core constituencies. McCain's plan to end the tax preference for employer-provided health insurance could be the basis of compromise with a similar plan advanced by Democratic Sen. Ron Wyden that has bipartisan support. McCain might also seek a bipartisan carbon reduction bill.

Much depends, whoever wins, on whether Democrats elect enough senators to overcome filibusters. Even more may ride on the course of the economy and the depth of the recession, which could scotch either candidate's proposals.