The civilian policy makers and generals who led Mr. Obama toward a troop escalation in Afghanistan during his first year in office — a decision that left him deeply distrustful of senior military leaders — have been replaced by a handpicked leadership that includes Defense Secretary Chuck Hagel and Gen. Martin E. Dempsey, the chairman of the Joint Chiefs of Staff.
President Obama was re-elected, relying on a coalition of voters that was broader than it was deep.
Democrats maintained an edge in party identification
Forty-five percent of those who voted for Mr. Obama were racial minorities, a record number, and he made gains among Hispanic and Asian-American voters.
Mr. Obama is also likely to win the popular vote, perhaps by two to three percentage points, once votes from California, Oregon and Washington are fully counted.
While the House of Representatives was called early in the night for Republicans, Democrats performed well in races for the United States Senate.
Tammy Baldwin, the Democratic candidate in Wisconsin, won her race and became the first openly gay or lesbian person elected to the United States Senate.
The votes counted so far in Ohio show an extraordinarily close race, with President Obama only about 1,000 ballots ahead of Mitt Romney as of 11:50 p.m.
But the vast bulk of precincts that have yet to report their results in Ohio are in counties that have gone for Mr. Obama.
The differences between national polls, which often showed a very tight race for the popular vote, and polls of swing states, where President Obama usually maintained an advantage,
Mr. Romney currently leads by 27 points in Tennessee, by 22 points in Kentucky, by 16 points in South Carolina and by almost 40 points in Oklahoma.
There are times in Kyrene when the technology seems to allow students to
disengage from learning: They are left at computers to perform a task but wind
up playing around, suggesting, as some researchers have found, that computers
can distract and not instruct.