It's official: Hurricane Katrina chased out a huge chunk of N.O. voters, remaking the region's electoral landscape

A new study by a political scientist confirms what election-watchers have suspected since Hurricane Katrina: The number of voters in the New Orleans area has fallen sharply, with African-Americans and registered Democrats losing the most ground.

The political landscape has shifted, especially in New Orleans.

Though voter rolls have remained virtually untouched since the flood, the comparison of voter turnout in the 2003 and 2007 gubernatorial contests shows that about 100,000 fewer people cast ballots last year in New Orleans and seven surrounding parishes than in the 2003 race.

Losses weren't borne equally by racial and party-affiliated groups, according to the analysis by University of New Orleans political scientist Ed Chervenak. For instance, a disproportionate loss among black voters across the region helped drive up white voters' share of the electorate, from two-thirds in 2003 to nearly three-quarterslast year.

Democrats also lost ground, with their participation sliding from 58 percent of the electorate in 2003 to 51 percent in 2007, the report shows. Republicans, meanwhile, saw their share of the voting population jump from 28 percent to 33 percent during the period.

With the number of voters across the rest of the state staying about even during the four-year span, the drop in turnout in the New Orleans area suggests the region has lost political clout since the 2005 storm, Chervenak writes in the report.

"The city's political voice was weaker in the last gubernatorial contest as voters here comprised only 6 percent of the state's overall electorate," compared with an average of 10 percent in the previous six races for governor, according to the report.

The study also offers a far clearer picture of how the voting population has shifted within city limits.

Reflecting patterns of damage from Katrina, turnout across Gentilly, eastern New Orleans and the Lower 9th Ward dropped nearly 60 percent from 2003 to 2007, while turnout across the rest of the city dipped between 27 percent and 36 percent, depending on the neighborhood, the study concluded.

Reshuffling the deck

After reviewing the report, Silas Lee, a local pollster and political strategist, said that although it's impossible to know how New Orleans' repopulation will affect future elections, the UNO study portends new dynamics in regional and statewide races.

"Anytime you lose 100,000 voters, it impacts influence," Lee said. "New Orleans will still be significant. However, you have somewhat of a different political ideology than you had pre-Katrina -- different kinds of voters with respect to social and economic and demographic status and political affiliation."

Christine Day, chairwoman of UNO's political science department, said the report offers a glimpse into how the region's politics might change after the 2010 U.S. census.

"It has really important implications for the redrawing of districts -- congressional districts and all the way down," she said. "Presumably, when districts are redrawn, Orleans Parish could lose clout. That said, the suburban areas probably will gain some clout, especially Jefferson and St. Tammany."

Unlike previous analyses of voter turnout, which generally have relied on precinct estimates to gauge participation based on race and party affiliation, the UNO study uses hard numbers compiled by the secretary of state. Records of who showed up to vote are matched with information provided in voter registration documents; which candidate each voter chose remains a secret.

Chervenak reviewed voter turnout data from 2003 and 2007 for eight parishes in the New Orleans area: Jefferson, Orleans, Plaquemines, St. Bernard, St. Charles, St. John the Baptist, St. Tammany and Tangipahoa.

The decline of more than 100,000 voters between the two elections represented a 23 percent drop across the region.

Not surprisingly, change figures varied widely by parish.

Faring best was St. Tammany, where 3 percent more voters turned out last year than in 2003, a bump that likely owes to the migration of residents from more flood-ravaged parishes. All other parishes saw drops in voter participation, ranging from a 2 percent dip in St. Charles to a 53 percent plummet in St. Bernard.

'More racially balanced'

In hard numbers, Orleans Parish showed the largest decline, with 60,000 fewer voters heading to the polls. That loss, Chervenak writes, accounted for most of the region's decline.

Across the eight parishes, the number of black voters dropped 41 percent between the 2003 and 2007 gubernatorial races, while the number of white voters dropped just 15 percent, the report states.

The analysis suggests there has been a sharp change in the racial composition of the region, particularly in Orleans Parish. In City Council districts B and C, a black majority in the electorate slipped away, and the districts are now almost evenly divided by race.

The city now has a more racially balanced electorate," Chervenak writes. "The days when local candidates could appeal to Orleans' overwhelmingly black electorate and receive a handful of white votes to win office may be a thing of the past."

He acknowledges that the analysis excludes children and teenagers who are too young to vote. But the "precise nature of the data makes it a robust measure of the population decline," he writes.

However, Allison Plyer, deputy director of the Greater New Orleans Community Data Center, cautioned against using the numbers to estimate population shifts across the region. With many variables affecting whether voters go to the polls, the measure can be wildly uncertain, she said.

"You can imagine that media spending and/or enthusiasm would differ greatly among certain populations," Plyer said. "It could be raining that day. Literally, weather on the day of the election could have an effect on turnout."