First they have to hold onto the 12 Democratic seats that are up for reelection. Most incumbent Democratic Senators have safe races. The most threatened seat is that of Louisiana Senator Mary Landrieu. For months Landrieu has maintained a single-digit lead over Republican John Kennedy six percentage points in the latest poll. Many Louisianans credit Landrieu with doing a good job after Hurricane Katrina; on the other hand, the Democratic base has lost many African-American voters. Prediction: narrow Landrieu victory.
Eleven races involve Republican Senate seats that Democrats have some likelihood of acquiring. The most probable pickup is in Virginia, where Senator John Warner is retiring. The contest pits two former governors Republican Bob Marshall and Democrat Mark Warner (no relation to John Warner). Mark Warner has consistently maintained a double-digit lead and is ahead by 27 points in the latest poll. Prediction: big Warner victory.
New Mexico Republican Senator Pete Domenici is also retiring. The Democratic candidate is Representative Tom Udall, Steward Udall's son, who he has run a strong race against Republican Steve Pearce. The latest polls show Udall up by 23 percent. Prediction: big Udall victory.
For months New Hampshire Republican Senator John Sununu has trailed Democratic challenger Jean Shaheen; she's currently leading by 14 percentage points. Sununu's only chance would be a big McCain victory in New Hampshire, but the most recent poll shows Obama leading by 11 percent. Prediction: Shaheen victory.
Colorado Republican Senator Wayne Allard is also retiring. The Democratic candidate is Representative Mark Udall Mo Udall's son and Tom Udall's cousin. Mark Udall has consistently maintained a single-digit lead over Republican Bob Schaffer; the latest poll shows Udall opening up a ten-point gap. Prediction: Udall victory.
At a minimum, Democrats will pick up four seats and have a 54-46 majority. However, in Alaska, ancient Republican Senator Ted Stevens is getting the race of his life from Democratic challenger Mark Begich, the Mayor of Anchorage. Polls have consistently showed this race to be within the polling margin of error. Obama is running surprisingly well in Alaska and could help Begich. Prediction: narrow win for Begich.
In Oregon, Senator Gordon Smith is in a tight race with Democratic challenger Jeff Merkley. The latest poll shows Smith up by four percentage points with 28 percent undecided. Obama is ahead in Oregon by six percentage points. If there's a big Democratic turnout, Merkley would benefit. Prediction: narrow win for Merkley.
When media personality Al Franken announced he was a candidate for the Minnesota Senate seat previously held by the late Paul Wellstone, many Democrats figure he would have an easy time defeating Republican Norm Coleman. But the latest polls show Coleman leading by ten percentage points. The good news for Franken is that Obama leads McCain by double digits; a big Democratic turnout will help Franken. Prediction: narrow win for Franken.
For months it looked like Maine Republican Senator Susan Collins would handily defeat Democratic Challenger Tom Allen, but the latest poll shows her margin has narrowed to 7 points. Obama leads McCain by 22 points. If Obama has coattails then Allen will win. Prediction: narrow win for Allen.
If everything goes right for Democrats they will pick up four more seats and have a 58-42 Senate majority. They have three chances to win the 59th and 60th seat and they all depend upon Obama's southern strategy. In Mississippi former Democratic Governor Ronnie Musgrove is locked in a tight race with incumbent Senator Roger Wicker who was appointed to serve out the unfinished portion of Trent Lott's term. This is another state where Obama voters may help a Democratic senatorial candidate as Obama trails McCain by only six points.
Prediction: too close to call.
North Carolina Republican Senator Elizabeth Dole is in a close contest with Democratic challenger Kay Hagan. The latest polls show Dole up by 10 points, but Obama is only down by 4 points. Prediction: too close to call.
Finally, Texas Republican Senator John Cornyn is having a tough time fending Democratic challenger Rick Noriega. One recent poll had Cornyn leading by two points. But Obama is running well in Texas he's down by only nine points. Prediction: too close to call.
An Obama landslide will give Democrats a chance of securing 60 Senate seats.