JACKSONVILLE, FLA. ? The most expensive presidential advertising campaign in history closes Tuesday after eight months with President Bush, Sen. John Kerry, their political parties and allied groups having spent more than $600 million on TV and radio commercials.

That’s triple the amount spent on such ads in 2000.

Still, for all the money, the race remains a statistical tie, even though Democrats have a spending advantage.

Since March, Kerry and the Democratic Party have poured about $250 million into TV and radio ads compared with about $240 million for Bush and the Republican National Committee.

Democrats have even more of an edge when spending by outside groups is included. Liberal organizations bought about $70 million worth of airtime, outpacing the $40 million or so spent by conservative organizations.

“The story this whole year has been the sheer volume of ads,” said Evan Tracey, president of TNS Media Intelligence/Campaign Media Analysis Group. “This is an election that I think changes politics.”

Despite the unprecedented spending, only about one-third of the country was inundated with commercials.

Ads ran on national cable networks, but most aired on local TV and radio stations in the 17 most competitive states. In the final two days of the campaign, commercials are focused on nine states — Florida, Ohio, Iowa, Pennsylvania, Wisconsin, New Hampshire, New Mexico, Nevada and Minnesota.