(AP) — The Baltimore Ravens won their second Super Bowl in 12 years by holding off the favored San Francisco 49ers 34-31 in Super Bowl 47 at the New Orleans Superdome.

Joe Flacco tossed three touchdown passes in the first half as the Ravens opened a 21-6 halftime edge, including a 56-yarder to Jacoby (jah-KOH'-bee) Jones just before halftime. Jones opened the second half with an electrifying 108-yard touchdown record, the longest kickoff return in Super Bowl history.

Then a power outage delayed play for 35 minutes, which seemed to breathe life into the Niners. Trailing 28-6 when the power went out, San Francisco came to life with 17 points over a 4:14 stretch of the third quarter to make it 28-23.

After Baltimore took a 31-23 lead, the Niners scored a touchdown to cut it to 31-29. San Francisco's two-point conversion failed. Baltimore added a late field goal and then in the final seconds took an intentional safety to make the final margin 34-31.

Flacco was named the Super Bowl MVP. He went 22 of 33 for 287 yards and the three scores. He's the sixth QB in 47 Super Bowls to throw for that many TDs in a half.

The Super Bowl was delayed because of a power outage Sunday, plunging parts of the Superdome into darkness and leading to a 34-minute delay in the biggest game of the year. The Baltimore Ravens were leading the San Francisco 49ers 28-6 when most of the lights in the 73,000-seat building went out with 13:22 left in the third quarter.

Auxiliary power kept the playing field from going totally dark, but escalators stopped working and the concourses were only illuminated by small banks of lights tied in to emergency service.

Players milled around on the sidelines, some took a seat on the bench, other on the field. A few of the Ravens threw footballs around.

A spokesman for the New Orleans power company said the outage appeared to originate in a failure of equipment maintained by stadium staff.