In the pivotal states, he benefited from the strong support of evangelical Christians and, just as important, an impressive showing among regular churchgoing Catholics and mainline Protestants.
Just as in 2000, roughly 42% of total votes were cast by people who attend church once a week or more. Those voters went overwhelmingly for Bush. Voters who went to religious services a few times a year or less went for Kerry by similar margins. The 14% who said they went a few times a month, went for Kerry 51% to 45%; they went for Gore last time.
Nationally, roughly 22 percent of the electorate was comprised of "White evangelicals" or "Born again" Christians, according to exit polls. Last time, the "religious right" made up 14 percent. It is not yet known whether this represents an actual increase or is just a result of the change in wording.
The importance of that vote can be seen in the fact that 21% of voters said "moral values" was the most important issue to them -- right on a par with the economy, terrorism, and Iraq.
But while Bush didn't improve much on his religious performance nationally, he did in a few pivotal battleground states.
Nationally, Kerry won 50% of the Catholic vote to Bush's 49%, according to exit polls. However, in Florida Bush beat him 55-45%. In Ohio, Bush apparently beat Kerry 53-46%.
Nationally, Catholics who attended church weekly voted 53% to 45% for Bush. In Ohio, the margin was 62% to 38%
In Colorado, a state the Democrats hoped to win, a quarter of the electorate was evangelical Christians, who voted 85% to 14% for Bush.
Nationally, 22% said they were evangelical or "born again." In Iowa, which the president narrowly won, 33% of the voters were evangelical.
The fact that Bush did as well among Catholics against Kerry--the first Catholic presidential nominee since 1960--as he did against Gore showed the strength of his efforts to woo traditional Mass-attending Catholics.
The Bush campaign made enormous efforts to win the Catholic vote this time, appointing 50,000 "team leaders" at the local level. The President made a point of visiting the Pope (in June 2004) and putting his picture on the campaign website with a headline "Catholics for Bush." Pro-life groups ran advertising in Catholic areas attacking pro-choice positions.
Though Kerry is the first Catholic presidential nominee since JFK, Bush's views on abortion and gay marriage were more in line with the Catholic hierarchy. Efforts by liberal Catholic groups and the Kerry campaign to court them were puny by comparison to pro-Bush efforts.
In a way, the significance of the overwhelming victory Bush had among evangelicals is obscured by the media focus on battleground states in recent weeks. Bush's strength among conservative Christians put huge swaths of the country simply out of reach for Kerry, requiring him to carry a high percentage of northeastern and midwestern states.
Of the 15 states with the highest evangelical population, all went for Bush - compiling a total of 121 electoral votes.