The victory in Italy's election Sunday and Monday marks a remarkable return to power for the 71-year-old Berlusconi, avenging his loss two years ago at the hand of the center-left.
"I'm moved, I feel a great responsibility," Berlusconi said Monday evening in a phone call to RAI public television. The media mogul remained out of sight, taking in the results at his villa outside Milan and, according to Italian news agencies, having a private dinner with key aides.
The victory attests to his political longevity - so much so that the German mass-circulation Bild on Monday compared him to the immortal character in the "Highlander" movies.
This was Berlusconi's fifth consecutive national campaign since 1994, when he stepped into politics from his media empire, currently estimated at $9.4 billion. He has fended off challenges to his leadership by his conservative allies, survived conflict of interests accusations and criminal trials.
During his last term he served a record-setting five years, until his 2006 defeat. During that term, Berlusconi made notable international gaffes and unpopular decisions, such as sending 3,000 troops to Iraq over the protests of thousands of Italians in the streets. The contingent has since been withdrawn.
This time he has ruled out sending new troops to Iraq, but his friendship with the United States is not in doubt.
Berlusconi once said that he agreed with the United States regardless of Washington's position. He calls U.S. President George W. Bush a friend, and his return to power is likely to make relations with Washington warmer, no matter who becomes the next American president.
The outgoing government of Premier Romano Prodi has had a colder relation with Washington, and Prodi never went to the White House, even though he has met with Bush in Rome and at international summits.
Berlusconi has also affirmed that he is one of Israel's closest friends in Europe.
On Monday, he said he would make the first foreign visit of his third term to Israel, to mark the Mideast country's 60th anniversary. It would be, he said, a show of support for "the only real democracy in the Middle East."
Berlusconi won strong victories in both houses of Parliament, despite a strong final sprint by his main rival, Walter Veltroni.
In the 315-member Senate, Berlusconi was projected to control 167 seats to Veltroni's 137.
In the lower house, Berlusconi's conservative bloc was leading by a margin of 7 percent, or 46 percent of the vote to 39 percent.
Berlusconi capitalized on discontent over the nation's stagnating economy and the unpopularity of Prodi's government.
"I think it was a vote against the performance of the Prodi government in the last two years," said Franco Pavoncello, a political science professor at Rome's John Cabot University. "Berlusconi won because he has a strong coalition and because people feel that on the other side, the government is going to take them nowhere."
A movement led by comedian-turned-moralizer Beppe Grillo had invited Italians to boycott the vote. But the nation remains highly polarized politically, and turnout in the two-day balloting was only 4 points behind the last national vote in 2006 - 80 percent compared with 84 percent, according to data from the Interior Ministry.
In his comeback, Berlusconi was helped by a strong showing by the Northern League, an important ally, which won about 6 percent of the vote, according to projections. The League has strong regional identification and people in Italy's wealthy northern regions have been complaining about Prodi's tax increases and the demise of Milan's hub Malpensa.
Berlusconi has no easy task ahead of him.
A laundry list of problems await, from cleaning piles of trash off the streets of Naples, which he has indicated will be his top priority, to improving an economy that has underperformed the rest of the euro zone for years.
The International Monetary Fund forecasts that the Italian economy, the world's seventh largest, will grow 0.3 percent this year, compared with a 1.4 percent average growth for the 15-country euro area.
Berlusconi will also need to make structural reforms that economists say are needed, such as streamlining the decision-making progress, and cut the costs associated with politics. A reform of the much-maligned current election law is also on the agenda.
In his postelection comments, Berlusconi said he was open to working with the opposition, and pledged to fight tax evasion, reform justice and reduce public debt. Berlusconi said he would reduce the number of Cabinet ministers to 12, including four women.