Tuesday's midterm election promises to be a real barnburner.

In a vote that could shift control of Congress to either the Republicans or Democrats, several races remain too close to call. The Democrats narrowly control the Senate now, while Republicans possess a slim majority in the House.

Battle lines are most sharply drawn in the fight for the Senate, where there were 50 Democrats, 49 Republicans and one independent, prior to the death of Minnesota Senator Paul Wellstone, a Democrat.

While the Republicans have made terrorism their big issue,

Democrats have turned the struggling economy into their most potent platform -- with questionable success.

Another flashpoint of the campaign is the federal budget, with the return of a deficit after four years of surpluses.

If Republicans gain control of Congress, Bush might be able to continue his tax cuts, which some Democrats now blame for the budget shortfall.

Meanwhile,

embattled brokers and accounting firms are shelling out millions of dollars to politicians who might go light on regulations.

The fate of

Social Security also hangs in the balance, and amid talk of privatization, some voters are wondering whether they'll see some cracks in the federal nest egg.

In a special election report,

TheStreet.com

takes a look at these key topics -- the economy, the federal budget and Social Security -- and also sheds light on where the Wall Street political action committees are throwing their money. For more on these issues, click on the above links.