With American voters almost evenly divided between the two major candidates for president, the campaigns and the media focus on undecided voters who could swing the election either way. This article outlines the make-up of the electorate; John Zogby's commentary looks at the voting behavior of certain groups of people. Zogby is president and chief executive officer of Zogby International, a public opinion polling firm.

With a voting age population of more than 200 million, the United States has a diverse electorate. In recent years, the media have divided the country into "red" and "blue" states to show voting preferences on national issues: red for Republican and blue for Democrat. But this is an oversimplification of America's political landscape. It does not, for example, show how close political races within those states can be. Although the winning candidate generally receives all of a state's electoral votes, nearly half of the voters in any red or blue state may have voted for the opponent. In the 2000 election, there were 14 states in which fewer than five percentage points separated the winning and losing candidates. A small shift in votes in a state where voters are almost evenly divided, then, can swing an election.

Political campaigns focus their efforts on two groups of voters: those who already support them - the party's "base" - and those who can be persuaded to support them, the "swing voters."

Both parties conduct polls to identify which voters might be won over to their side of the ballot. Throughout the campaign, pollsters seek out information on voters' lifestyles, their attitudes on issues, and their preferences for president. The campaigns use this information to plan strategies for reaching undecided and independent voters; the media use the data to present a picture of how the race for the White House is going and to predict the winner.

Experts agree that the strongest influence on voter behavior is party identification. Currently, American voters identify themselves in roughly equal numbers as Republicans, Democrats, or independents unaffiliated with either of the major parties. Although studies suggest that independents actually tend to vote consistently for one party's candidates over the other, still, a number of these voters will realign themselves when they feel there are serious problems in the country or in their community that are not being adequately addressed. It is this portion of the unpredictable electorate, about 10 percent of all voters, that candidates target most heavily, tailoring their campaign messages to what pollsters have determined are most likely to be persuasive.

There are, in fact, some regional voter characteristics: the residents of Pacific coast states and the northeastern states tend to be more liberal on social and economic issues, while those in the South tend to be more conservative; swing states tend to be those with a balance of both rural and large urban areas. But because of the mobility of Americans (each year nearly one-fifth of the U.S. population moves), the influx of immigrants who become voters, and the influence of the national media, voting patterns change from election to election.

For example, following World War II, Florida was a resolutely conservative Republican state, only three times awarding its electoral votes to a Democratic presidential candidate. But in the past decade, thousands of retirees from northern cities have moved there, and its African-American and non-Cuban Hispanic populations have doubled. These groups traditionally support Democratic candidates, and, as the 2000 election showed, Florida is now an important swing state.

Looking beyond regional voting history, pollsters find more accurate indicators of how a citizen will cast his or her vote by looking at age, gender, education level, income, ethnicity, and other demographic characteristics that affect political opinions. Persons who identify themselves as evangelical Christians, for example, are more likely to vote Republican; college educated women are more likely to be liberal on social issues; affluent males are more likely to be economically conservative.

This election—like many before it—will be decided by a handful of groups. Expect Hispanics, African-Americans, Catholics, young voters, rural and suburban voters to all impact the race for the White House. Add to this that these groups only impact heavily in battleground states, and you glimpse which groups hold the keys to power in 2004.

Three groups favor Democrat John Kerry over Republican George W. Bush by lopsided margins: African-Americans, Hispanics, and young voters. Among those groups, the real race isn't about winning them over, but about getting them to the polls—high voter turnout is the key for a Democratic win; low turnout among these groups, and the Republicans will be in office for four more years.

The race promises a political street-fight in 20 swing states. There, suburban voters are the real battleground: Among suburbanites, Mr. Bush leads Mr. Kerry.

Hispanics will be the most closely watched demographic this election. Mr. Bush heavily courted Hispanics during his term. He did this for good reason: In 2000, Hispanics passed African-Americans as the largest minority group in the U.S. Hispanics represented just 7% of the 2000 vote, a number expected to grow this election.

The African-American vote is critical for Democrats. African-Americans supported Mr. Gore by a 9-1 margin, and will support Mr. Kerry by a similar margin. High African-American turnout can sway the race Mr. Kerry's way in Florida, Michigan, Missouri, North Carolina, Ohio, Pennsylvania, Tennessee, and Virginia.

White Evangelical Christians are a key constituency that favors the Republican Party. A number of Bush administration initiatives reflecting conservative social and cultural values elicit strong support from this group. Some Republican strategists have claimed that the nearly four million white Evangelicals who did not vote in the 2000 election cost Bush the popular vote. Whether or not that number is accurate, Republicans want to maximize the turnout of Evangelicals at the polls in 2004.

Catholic voters have become one of the top swing groups—largely because they are a bellwether that votes the way the nation votes. In 2000 Mr. Gore won here by two points. Since then Mr. Bush has courted Catholics—a group that matters in nearly every swing state. Despite being Catholic himself, Mr. Kerry currently trails Mr. Bush. Only in swing states Arkansas, North Carolina, Oregon, Tennessee, Virginia, Washington and West Virginia do Catholics not comprise at least one-quarter of voters.

Rural voters—key to former President Clinton's victories—will be a critical group. Mr. Kerry is trying to reach rural voters through economic messages, and many rural voters live in areas hard-hit by the recession.

Young voters may also prove important in this election. They have been heavily targeted by non-partisan groups like Rock the Vote and partisans like filmmaker Michael Moore. In 2000 Mr. Gore edged out Mr. Bush by 48% to 46%, and at the time of this writing, Mr. Kerry appeared to have a solid lead over Mr. Bush.

None of this means that a late surge by one candidate, or the emergence of an unexpected trend, can't shift the race; however, as it stands today, expect strategy in both camps to focus on these constituencies in the remaining days before November 2.

The opinions expressed in this article do not necessarily reflect the views or policies of the U.S. government.