As we get closer to Election Day, the unaffiliated and undecided sliver of the electorate will be scrutinized ad naseum. Estimates of $1 billion may be spent on advertising, much of it trying to convince less than 10% of voters that Barack Obamaor Mitt Romney will be the worse choice for President.

But in our hyper-polarized electorate, the more decisive factor will be turn out from voters who would be expected to choose one party over the other. We already see both Obama and Romney concentrating on their respective base voters. That's why Obama has come out for same-sex marriage and hammered Republicans about holding down interest rates on student loans. Meanwhile, Romney has yet to make any overt moves to the middle for fear of losing support from conservatives. As you will read below, small percentage decreases in turnout of base voters can account for millions of votes.

Romney and Obama are tied in the national average of polls, so every vote will matter. My Washington Times/JZ Analytics polling has the two within one point. While it's way too soon to make predictions about outcome or turnout, we can develop some models of turnout from various core groups, and how each may impact the outcome. These projections will be my benchmark for further analysis moving toward Election Day. For now, I'll stay with the national popular vote and not individual states. That will come later as I do more Washington Times/JZ Analytics polling. It's also important to note the overlap among voting groups I will be looking at, which will be greater between some groups than others.

In 2008, 133 million votes were cast for President. Since the total vote rarely goes down and the turnout for Obama was so high among new voters four years ago, projecting a turnout of 133 million again is reasonable.

In this piece , I'll examine the key groups Obama must turn out to win. Tomorrow, I'll look at how support and turnout from the GOP base will impact Romney.

For Obama, vital targets are Hispanics, African-Americans, the Creative Class and most critically voters ages 18-29.

In 2008, Hispanics made up 9% of the electorate, and Obama won 69% for eight million votes. Now, he is taking 61% of Hispanic voters, which would be 7.3 million votes. Some suggest Republican policies on immigration may push Hispanic turnout to 11% of the vote, which based on Obama's current polling would total 8.9 million. But with Hispanics hit hard by the economy, their percentage of the vote could drop as low as 8%, or 6.5 million votes for Obama. From high to low is a difference of 2.4 million votes for Obama, more than enough to swing the entire election.

African-Americans are a more stable electorate because they have a longer history of voting and a strong loyalty to Obama. They were 11% of all voters in 2008, and that will likely repeat this year. Obama won 95% of African-Americans then, and polls have him at 91% now, or 13.3 million votes based on the 2008 turnout. If the African-American total of all voters drops from 2008, Obama loses approximately 1.2 million votes for each percentage point decrease.

The final Democratic base cohort is that economist and social scientist Richard Florida dubbed the Creative Class. For this purpose, I'll define them as mostly white, earning more than $75,000 and college educated. Their exact vote is tougher to quantify, but important enough to weigh. In 2008, the Creative Class accounted for 26% of the electorate and gave Obama 61% (about 21 million votes.) Now, Obama is polling at 55% (18 million votes.) For every percentage point drop of the total vote from the Creative Class, Obama loses nearly three million votes.

Voters ages 18-29 are Obama's most volatile core group. They set a record in 2008 by accounting for 19% of the vote, of which Obama won 67% (about 16.9 million.) Obama now polls at 46%-40% of those 18-29 (still enough to lead Romney.) Based on the 2008 turnout and today's polls, Obama would suffer a fatal loss of more than five million votes. It gets worse for Obama if, as may well happen, their turnout drops to 17% (10.4 million Obama votes) or to 16% (9.8 million Obama votes.) Obama cannot sustain a loss of seven million from under 30 voters and win this election.

Obama has one other worry with young voters: Libertarian candidate Gary Johnson. While overall Johnson may take more votes from Romney, that may not be true with young voters. When you want to change the system and not just the politicians, as some young voters do, casting a third party vote is not throwing it away. This age group has libertarian leanings. Johnson may score on college campuses, and not just because he would legalize marijuana.