MANCHESTER, N.H. – A judge gave state Democrats the go-ahead Thursday to question high-ranking Republicans in a civil suit over the jamming of Democrats’ phones on Election Day 2002.

Three former GOP officials have already been sentenced in the phone jamming scheme. In the civil suit, state Democrats want to know who knew about the plan.

They point to a record of phone calls that show national GOP official James Tobin, one of those convicted, made two dozen calls to the White House within a three-day period as the phone jamming operation was carried out and then abruptly shut down.

The national Republican Party, which paid millions in legal bills to defend Tobin, who is from Bangor, Maine, said the contacts involved routine election business and that it was “preposterous” to suggest the calls involved phone jamming. Tobin, who was sentenced in April to 10 months in federal prison, remains free on bail pending an appeal to the 1st U.S. Circuit Court of Appeals in Boston.

Robert Kelner, a Washington, D.C., lawyer representing the Republican National Committee, said some of the officials the Democrats want to question may fight being deposed.

Democrats want to question the former associate director of the White House Political Affairs Office, Alicia Davis, and to see her phone records and those of her then-boss, Ken Mehlman, now RNC chairman.

Also on their list: Edward Gillespie, who was RNC chairman when the decision was made to pay Tobin’s legal expenses; Terry Nelson, former executive director of political operations for the RNC and now a political strategist for Sen. John McCain; and Chris LaCivita, former national political director for the National Republican Senatorial Committee who went on to develop the Swift Boat veterans TV campaign against Democratic presidential nominee John Kerry in 2004.

An aide to Mehlman referred questions to the Justice Department, which won convictions in the criminal case. Gillespie was not immediately available for comment Thursday.

The Democratic National Committee praised the judge’s decision.

“Today’s ruling brings us one step closer to finding out who knew what and when they knew it on the criminal scheme to disenfranchise New Hampshire voters,” said Karen Finney, the DNC’s communications director.

The lawsuit seeks compensation for alleged GOP interference with telephone systems amid a hotly contested U.S. Senate race between then-Gov. Jeanne Shaheen and Republican John Sununu. Sununu won by about 20,000 votes.

The calls tied up phone lines for more than an hour as Democrats and the nonpartisan Manchester firefighters’ union were offering rides to the polls.

Tobin was convicted in December on two felony telephone harassment charges. He was sentenced to 10 months in prison but is free while his appeals are pending.