Updated at 7:16 p.m. AKST: President Obama is projected to win Ohio, giving him more than the 270 electoral college votes needed to win re-election.

Updated at 7:12 p.m. AKST: CBS News projects President Obama wins the key state of Iowa's six electoral votes, as well as Oregon's seven electoral votes.

Updated at 7 p.m. AKST: CBS News projects Mitt Romney will win North Carolina, making it the first battleground state to fall into his column. Romney is also projected to win Idaho.

President Obama, meanwhile, is projected to win California, Hawaii, New Mexico and Washington state.

Updated at 6:50 p.m. AKST: Right now, CBS News' Dean Reynolds reports, President Obama is leading in three significant north central Ohio counties with an older, whiter population -- but one that retains ties to the auto industry and organized labor. Mr. Obama won those counties -- Wood, Sandusky and Ottawa counties -- in 2008, and he is winning them again.

Furthermore, a top official from the Ohio secretary of state's office tells Reynolds there are more outstanding votes from urban areas than rural. This is another good sign for Mr. Obama, since urban areas are typically Democratic. An Obama campaign source says they have met their early voting projections, Reynolds reports. Ohio, the source said, is looking good.

Meanwhile, in Virginia, an Obama campaign spokesperson tells CBS News' Nancy Cordes turnout will exceed 2008 turnout, which is a good sign for the president.

Updated at 6:30 p.m. AKST: CBS News projects President Obama will win Minnesota, bringing his projected electoral tally at this point to 167. CBS News projects Mitt Romney will win Arizona, bringing his tally to 184.

Updated at 6:15 p.m. AKST: CBS News projects the battleground state of Iowa is leaning toward President Obama.

Updated at 6:08 p.m. AKST: CBS News projects Mitt Romney will win Missouri, bringing his electoral college tally to 173.

Updated at 6 p.m. AKST: CBS News projects Mitt Romney will win Utah and Montana, bringing his electoral college tally to 162.

According to projections, Mr. Obama's electoral college tally stands at 157.

The battleground state of Nevada, where polls are closed, is now leaning toward Mr. Obama. Polls have also closed in the battleground state of Iowa, but CBS News cannot yet project the outcomes there.

Iowa, with six electoral votes, gave Mr. Obama his first big victory in the 2008 caucus, and he won the state in the 2008 general election by 9.4 points. Several factors help explain why the state, which has historically been so kind to Mr. Obama, remains tight, according to CBS News consultant Jeanne Zaino.

While CBS News' early exit polling shows that women favor Mr. Obama by a large number (14 points), his support among men is down seven points from 2008. Similarly, while young people aged 18-29 favor the president (56 percent to 40 percent), those 64 and older favor Mitt Romney.

In the rural and suburban areas which may decide this race, Romney is outperforming Mr. Obama. At the same time, however, independents -- which are key to electoral victory -- are breaking 53 percent to 43 percent for Mr. Obama.