Super Tuesday Preview: How to Interpret Tonight's Returns

    As the vote comes in tonight, here's how to interpret the returns:

    GEORGIA -- 7 PM

    Republicans: This is one of the few states in which all three candidates have a chance to win. If McCain wins here -- in addition to all the other states where a victory for him is virtually assured --  it's going to be a long, long night for the other two.

    Democrats: Anything other than a huge Obama victory will be a shock. This should be his second strongest state after Illinois.

    THE 8 PM EASTERN BLOC -- MASS., N.Y., CT., DEL., N.J. (all close at 8 pm ET except for NY)

    Republicans: McCain is expected to strongly sweep the winner-take-all three of NY, Ct., and NJ. Mass. should go for Romney. Delaware's predelictions are unknown, though few delegates are at stake.

    Democrats: NY will go for Hillary big; NJ should go for her by a smaller margin (though if it's close she may be in trouble elsewhere). Ct., Mass., and Delaware should give the first indication of how the night is likely to go for the Democratic contenders. A sweep by either candidate will be a sign that the tide is running in his or her favor. A Mass. loss is more embarassing to Obama than a Ct. loss is to Clinton because of the Kennedy endorsement.

    THE SOUTHERN PRIMARIES -- ALA. TENN., ARK. (all close at 8 pm ET)

    Republicans: As in Georgia, Huckabee -- and to a lesser extent Romney -- must make their stand here. Any McCain victories in these states are just icing on the cake.

    Democrats: Tennessee and Arkansas are expected to go for Hillary; Obama is expected to win Alabama. Any results different from these will be news -- though the results will be eclipsed by results elsewhere.

    THE MIDWEST -- ILLINOIS AND MISSOURI (close at 8 pm ET)

    Republicans: To have any hope of derailing McCain, either Huckabee and Romney must win Missouri -- another winner-take-all state for the GOP. Illinois seems likely to go for McCain; any other result would be a sign his campaign could be unexpectedly floundering.

    Democrats: Illinois will go big for favorite son Barack. The results in Missouri, a swing state, are hugely significant psychologically and are one of the key points of interest of the night.

    THE KEY CAUCUS STATES -- MINNESOTA, COLORADO, NEW MEXICO (DEMS ONLY)

    Republicans: Romney has done much better in caucus states than in primary contests. He needs to replicate those results here.

    Democrats: Obama has targeted all three of these contests and needs victories in these states more than Clinton to stay even in delegates with Clinton for the evening. New Mexico, with its huge Hispanic population, should be a harbinger of how the results may go in Arizona and California.

    THE WEST -- ARIZONA (CLOSES AT 9 ET) AND CALIFORNIA (CLOSES AT 11 ET)

   Republicans: McCain obviously wins Arizona. Without a win in California, Romney can pack it in -- and he still might have to, if he only wins the Golden State narrowly and the delegates split evenly. (For the GOP, California is winner-take-all by congressional district.)

    Democrats: These results are likely to dominate the Eastern news Wednesday morning since they will come in late. As in Missouri, both candidates need victories here -- especially California.

   There are other states at stake, such as Oklahoma, Utah, Alaska, North Dakota, and Idaho, among others. They will receive less attention from the national media but offer Romney and Obama a chance to do better against the putative front-runners than many other states either because of their size or because they're caucus states. Thus they have importance to these campaigns, even though relatively few delegates are at stake.


    BOTTOM LINE:

    Republicans: McCain will amass a huge lead in delegates, thanks to his winner-take-all victories in the east. The key as to whether the race continues is whether Huckabee and Romney can win a majority of the five southern primaries (Ga., Ala., Ark., Tenn.,, Okla.) and then beat him first in either Missouri or Illinois -- and then California. Unless that happens, McCain is virtually unstoppable.

    Democrats:  The key to the race is who wins California -- and then proceeding back eastwards -- who wins Missouri and two of the three of NJ, Mass., and Ct.

    If Clinton has a lead of over 150 delegates at the end of the night (including superdelegates committed already), she will be tough to stop, given the Dems' proportional representation scheme. If the race is roughly even in delegates at the end of the night (including superdelegates already committed), Obama is in good shape.