When Oscar winner Kevin Costner testified on Capitol Hill on Wednesday about cleaning up the Gulf of Mexico oil spill, the “Field of Dreams” star insisted his expertise didn’t come about just because “I heard a voice in a cornfield.”

Rather, Costner personally has spent more than $20 million to fund his business, Ocean Therapy Solutions, which developed a machine that he says can separate oil from water. And when he appeared before the House Science and Technology Subcommittee on Energy and Environment, Costner really drove home the fact that he spent his own cash.

“The price tag would be over $20 million, and I paid for it,” he said of the machine in his opening remarks.

“I don’t know how much they’ve spent, but I’ve spent all my profits,” Costner added, referring to oil industry efforts to develop cleanup technology.

“I don’t know if I’m embarrassed about the money I spent, I don’t know if I’m proud of it, but at some point I’m exhausted,” Costner later said.

Panel members seemed impressed with Costner’s efforts, and Rep. Dana Rohrabacher (R-Calif.) praised him for using his fame for a good cause.

“Well, it was my money, actually,” Costner replied.

Now, don’t feel too bad that Costner spent so much dough: He made $15 million just for his 2002 film “Dragonfly,” according to the Internet Movie Database.

And the iPhone Goes to …

Rep. John Fleming is really good at making friends.

At least on the Facebook. And also the Twitters and YouTubes.

The Louisiana Republican nabbed first place in the House Republican Conference’s New Media Challenge, which featured 56 Members battling it out to gain the most Facebook friends, Twitter followers and YouTube subscribers in a six-week span. The Conference awarded the freshman an iPhone for his social networking skills, while second place winner Rep. Phil Gingrey (Ga.) won a flip camera and Texas Rep. Lamar Smith nabbed a set of steak knives (symbolizing how Republicans are at the “cutting edge” of new media) for placing third.

Fleming spokesman Jamie Hennigan tells HOH that his boss’s key to success came about a year ago, when he introduced legislation during the health care debate requiring Members who voted for the public insurance option to enroll in it. Fleming set up a petition page on his website, and 4 million people signed and gave their contact information.

When the New Media Challenge began, Fleming had a hefty list of potential online friends. “The Congressman’s extremely excited. He’s been tracking this thing closely from day one, I can promise you that,” Hennigan said.

Meanwhile, House Democrats began a similar contest earlier this week to close the social networking gap (leading GOPers to gloat, just a little).

“If they want to get into business of copying Republican ideas, we have plenty they can choose from,” Hennigan joked.

Better Than a Post Office

Ask and ye shall receive, especially if you are an appropriator such as Reps. Debbie Wasserman Schultz (D-Fla.) or Dutch Ruppersberger (D-Md.). The two were on hand as officials unveiled the low-priced sub shop in the Rayburn House Office Building on Wednesday, and after Ruppersberger suggested that the shop name sandwiches after them … poof, the cafeteria folks complied.

Wasserman Schultz has long championed cheaper menu offerings for House cafeterias and praised the opening of Heroes on the Hill to better serve broke, overworked Hill staffers.

“I’m a Jewish mother, and eating is important in my culture,” she told HOH between bites of the $4.95 Italian sub. (She gave it the thumbs-up, by the way.) “I look at what my staff eats — if they eat at all — and my heart goes out to them. Now they will have healthier and more affordable options.”

Ruppersberger told the crowd, which included House Chief Administrative Officer Dan Beard and officials from Restaurant Associates, the cafeteria vendor, that he would stop singing jingles from the sandwich shop Subway during appropriations hearings now that the House has its own bargain outlet. “Maybe we’ll get sandwiches named after us,” he mused.

A few hours later, a CAO spokesman informed HOH that the shop would indeed name two of its offerings after the legislative duo. As of yet, the sandwich tributes have yet to be named, but might HOH suggest the “Veggie [Ruppers]Burger” and the “Little Debbie”?

Overheard on the Hill

“Whatever the hell this says.”

— 87-year-old Rep. Ralph Hall (R-Texas), reading from his prepared opening statement at a House Science and Technology subcommittee hearing Wednesday.

“Weiner, Chaffetz Call for End to Mohair Subsidies: A Democrat, a Republican, and a Goat Speak Out”

— The title of a media advisory sent Wednesday, alerting reporters to a press conference today at which Reps. Anthony Weiner (D-N.Y.) and Jason Chaffetz (R-Utah) and a “live ‘mohair’ goat” will be speaking.

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