The hotly contested race between Joe Donnelly and Richard Mourdock for U.S. Senate won’t be decided until Nov. 6. But Indianapolis television stations already can declare themselves winners based on the huge amounts of campaign cash being spent to advertise on their channels.

Throw in the Indiana governor’s contest between U.S. Rep. Mike Pence and former Speaker of the Indiana House John Gregg, and the stations have reaped a collective windfall of at least $4 million from the candidates, according to Federal Communications Commission filings. And that's not counting the estimated $4.5 million that numerous Political Action Committees have spent with them to support both state and federal candidates in Indiana.

The amounts candidates are spending on television advertising are available this year for the first time online. In the past, those interested in obtaining the figures had to physically travel to each station to get copies.

The FCC doesn't require broadcasters to upload files in a single format, however, making it difficult to get a precise accounting of spending.

Still, the records provide a glimpse into just how important the seat that veteran U.S. Sen. Richard Lugar lost to Mourdock in the Republican primary is to both Republicans and Democrats. It’s one of four seats the GOP needs to take control of the Senate.

Through Monday, Donnelly and Mourdock together had shelled out about $1.8 million—roughly $900,000 each—to advertise on WRTV-TV Channel 6, WISH-TV Channel 8, WTHR-TV Channel 13 and WXIN-TV Channel 59, according to FCC filings.

“I would say it’s the most expensive Senate race in history,” said Bill Perkins, president of Indianapolis-based media-buying firm Perkins Nichols Media, who bought spots for Lugar in the primary. “The money Mourdock spent in the primary was the most ever spent, and this far exceeds that.”

Among the more lucrative spots was a 30-second ad during WTHR’s broadcast of Sunday Night Football that cost Donnelly $4,000.

The amounts the candidates are spending undoubtedly are much larger when considering spots bought on cable television stations and on local networks in metropolitan areas outside of Indianapolis.

In addition, political action committees also are forking out big bucks to help their candidate get elected, raising the stakes even more.

Donnelly and Mourdock collectively have spent about $700,000 to advertise on WTHR—the most of any local television station. But the roughly $1.2 million various PACs have paid the station underscores the importance of the race even more.

The conservative Club for Growth Action PAC has spent more than $350,000 with WTHR while the left-leaning Center Forward tallied up a bill of nearly $300,000.

A spokesman for the Washington, D.C.-based Club for Growth declined to specify how much the group has spent locally but said it has contributed $1.7 million statewide to back Mourdock.

"It's one of the races [nationally] that Club for Growth Action has invested most heavily in," spokesman Barney Keller said.

Donnelly and Mourdock also have spent big locally with WISH, totaling more than $620,000 between them.

Only one of the four general managers—Larry Blackerby at WRTV—returned phone calls seeking comment on the advertising dollars.

“Every election year brings money in,” Blackerby said. “That’s been going on for a couple of months in the battleground states. Whereas here, it’s only picked up in the last couple of days [since mid-October].”

To be sure, President Obama and challenger Mitt Romney are dumping loads of money into swing states such as Florida, Ohio and Wisconsin.

Romney is expected to carry Indiana, evidenced by the lack of attention the two are giving central Indiana. None of the four local stations in Indianapolis have reported advertising spending by either Obama or Romney, according to the FCC.

But the television broadcasters more than make up for the lack of spending by the presidential candidates with the race for Indiana governor.

Pence and Gregg have spent nearly $1.2 million each with the four local stations, with WTHR capturing about $900,000 of the $2.4 million total.

Federal law mandates that candidates are to be given the lowest rate available for a certain time spot. But it’s open season on PACs, said Perkins the media buyer.

“For a PAC spot, stations can charge anything they want,” he said, “and they will charge obscene rates.”