New Update: Can McCain win?

First some background: For the past week we've been following the state-by-state polls, using Yahoo! numbers. We wouldn't want to go to Vegas on it, but John McCain's chances are looking better than they did one week ago.

You can follow along by playing with the electoral map at Yahoo! (I used the polls that pop up when you mouse over a state.) Then I jotted down the numbers and went to the part of the site where you can create your own scenario.

Again, it's the numbers from Yahoo! and this is a snapshot as of Sunday evening, Nov. 2. There are tons of polls out there, with wildly different findings. Also, it could all change when new numbers are released in the last couple of days.

Both sides will tell you to assume nothing. Answering a survey over the phone is a lot different than throwing on a jacket, heading out to your precinct and waiting in line to vote.

But getting back to Yahoo!, we have to fill in the gray on the "create your own scenario" map: The Yahoo! political dashboard doesn't have poll numbers for five regions. We'll give Idaho to McCain. We'll give Hawaii, Maryland, Vermont and Washington, D.C. to Obama because that seems to be the voting pattern in those areas.

Indiana and Missouri were battlegroud-leaning Obama a week ago. Now they are leaning McCain, but have been very close throughout. Yahoo! also posted poll numbers for South Dakota for the first time. They favor McCain.

Electoral Votes: Obama -- 353, McCain -- 185

The candidates need 270 electoral votes to win, so McCain has to flip a significant number of states. Start with the very close states, which have Obama leading only slightly at the moment, with margins:

North Carolina +0.3

Virginia +3.8

Florida + 4.2

Ohio +4.2

Electoral Votes: Obama -- 278, McCain -- 260

Virginia has become much more competitive in the past week, and McCain also gained in Ohio since Thursday. Florida has drifted toward Obama a bit in the past week. As you see, even if everything falls McCain's way above, Obama still comes away with an electoral win. McCain will have to dip into the next tier of Obama-leaning states, based on the Yahoo! numbers:

Colorado + 5.5

Electoral Votes: McCain -- 269, Obama -- 269

Colorado gets its own line because it reflects the tipping point. Keep in mind we're using one set of poll numbers on one day, but if John McCain can capture states where he's within 5.5 percentage points of Obama as of Thursday afternoon (five days out), he'll catch Obama in the electoral college.

McCain still needs to capture one more electoral vote based on what we've told you so far. Here's the states next in line in the Yahoo! poll:

Nevada: +5.8

Pennsylvania +7

New Mexico +7.3

Anyone one of these states puts McCain over 270, but an upset in Pennsylvania makes things much easier for the Republican. Without those 21 electoral votes, McCain likely needs two of three from the Western swing states of Colorado, Nevada and New Mexico. If he captures Pennsylvania, he doesn't have to worry about any of them.

Prospects fade for McCain after that. New Hampshire is next in line with a 10.7 lead for Obama. Then comes Wisconsin, which favors Obama by 11 percent.

The next two states are Minnesota (+11.5) percent and Michigan (+13 percent). Yahoo! numbers give Obama a 15.3 percent lead in Iowa.

From here, it looks like McCain needs to carry Missouri, Florida and North Carolina. And he needs 2-of-3 from Ohio, Pennsylvania and Virginia. Plus he may need a state or two out West.