Sunday's runoff pits a veteran center-left leader, Pier Luigi Bersani, 61, against the 37-year-old mayor of Florence, Matteo Renzi, who has campaigned on an Obama-style "Let's change Italy now" mantra.
Nearly all polls show Bersani winning the primary, after he won the first round of balloting Nov. 25 with 44.9 percent of the vote. Since he didn't get an absolute majority, he was forced into a runoff with Renzi, who garnered 35.5 percent.
After battling all week to get more voters to the polling stations for round two, Renzi seemed almost resigned to a Bersani win by Sunday, saying he hoped that by Monday "we can all work together."
Bersani, a former transport and industry minister, seemed confident of victory as well, joking about Berlusconi's flip-flopping political ambitions by asking "What time did he say it?" when told that the media mogul had purportedly decided against running.
Next year's general election will largely decide how and whether Italy continues on the path to financial health charted by Premier Mario Monti, appointed last year to save Italy from a Greek-style debt crisis.
The former European commissioner was named to head a technical government after international markets lost confidence in then-Premier Berlusconi's ability to reign in Italy's public debt and push through sorely needed structural reforms.
Berlusconi has largely stayed out of the public spotlight for the past year, but he returned with force in recent weeks, announcing he was thinking about running again, then changing his mind, then threatening to bring down Monti's government, and most recently staying silent about his political plans.
His waffling has thrown his People of Freedom party into disarray and disrupted its own plans for a primary—all of which has only seemed to bolster the impression of order, stability and organization within the center-left camp.
A poll published Friday gave the Democratic Party 30 percent of the vote if the election were held now, compared with some 19.5 percent for the upstart populist movement of comic Beppe Grillo, and Berlusconi's People of Freedom party in third with 14.3 percent. The poll, by the SWG firm for state-run RAI 3, surveyed 5,000 voting-age adults by telephone between Nov. 26 and 28. It had a margin of error of plus or minus 1.36 percentage points.
It's quite a turnabout for Berlusconi's once-dominant movement, and a similarly remarkable shift in fortunes for the Democratic Party, which had been in shambles for years, unable to capitalize on Berlusconi's professional and personal failings while he was premier.
But Berlusconi's 2011 downfall and a series of recent political party funding scandals that have targeted mostly center-right politicians have contributed to the party's rise as Italy struggles through a grinding recession and near-record high unemployment.
Angelino Alfano, Berlusconi's hand-picked political heir, seemed again exasperated Sunday after a long meeting with his patron over Berlusconi's plans. News reports have suggested Berlusconi might split the party in two and re-launch the Forza Italia party that brought him to political power for the first time in 1994.
"We have to work to reconstruct the center-right, and reconstructing it means having a big center-right party," not a divided one, Alfano said.
He added that Berlusconi didn't say one way or another if he would run himself. "It's his choice," he said. "If there are any decisions in this regard, he'll be the one to say so."
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