Indy Car racing is dominated by Dario Franchitti, Scott Dixon, Tony Kanaan, and Dan Wheldon - all foreigners. The only American to win this year is Sam Hornish, who isn't exactly beloved by fans after snatching last year's Indy 500 victory from Marco Andretti is the last few hundred yards. Danica is the only reason many people even watch these races, and she's never won. If she did, Indy Car racing would see a surge in popularity overnight. 

>>Danica is the only reason many people even watch these races, and she's never won. If she did, Indy Car racing would see a surge in popularity overnight. 

I'd like to see Danica Patrick win soon.  She is always a feisty competitor who puts a lot of pressure on herself to win.  You can tell because she's always frustrated when a problem occurs that keeps her from having a chance to win.  That's happened three times recently:  at Nashville when Ed Carpenter, who was like 3 or 4 laps down, refused to let her pass him with only a few laps left,  at Michigan and Kentucky in back to back races (the same ones where Franchitti flipped his car) where tire problems cost Danica a possible chance at victory.

And you forgot to mention that Champ Car is dominated by Sebastien Bourdais and Robert Doornbos-both foreigners.  In fact the Champ Car series I think has even less Americans than the Indycar Series.  Most of the Americans in Champ Car have retired and AJ Allmendinger left for NASCAR.  But some parity could come to Champ Car next year.  Bourdais is going to Formula 1.  I hope he does well there.  I hear Bourdais is replacing struggling American driver Scott Speed, but I'm not sure and I don't know if Speed will be in F1 next year or not.

Actually soccer is the most highly viewed sport in the world even without America's viewership!  NASCAR is more popular that open wheel racing for many reasons, including the ones mention in other posts. Other reasons include the CART and IRL split which left fields as small as 16 cars in some events and made the Indy 500, once the largest single day sports even in the world(yes, even bigger than the Superbowl), just another race. The stands were half filled at almost every race and sponsors dont like empty seats. 

Another of NASCAR's attractions is the rough and tumble nature of the racing. You can bump draft, swap paint, tag the wall and engage in all manner of ontrack shennanigans which makes for very exciting racing. In open wheel that is impossilble. The cars are VERY fragile and not designed for contact racing.

In Open Wheel it generally becomes obvious who is going to win with plenty of time left. NASCAR is generally not decided until the last few laps and many races are won by one second or less. Due to the high number of yellows compared with open wheelers, pit strategies become a huge part of the suspense. People want to see racing, not domination by a single driver, especially a foreigner. Juan Pablo Montoya already has a huge "hate" club, which is actually good for him, his team and NASCAR in general. It doesn't matter why people watch as long as they watch.

NASCAR has 36 races and, for the last few years, "The Chase", which makes it a ten driver mad dash for the title in the last ten races of the season. Open wheelers have less than half that schedule and the championship has generally been decided by the three quarter point of the season barring unforseen problems.

Women make up a HUGE part of the NASCAR fanbase and virtually none of teh open wheel base. That's because your wife can relate to Jeff Gordon winning in a Monte Carlo just like hers whereas your wife has no clue what the hell that funky little car is and has never seen a Williams-Honda on a lot.

Finally, NASCAR is a uniquely American sport. No other country in the world has anything like it and it's popularity in Europe is growing as a spectator sport also. Toyota has thrown its hat into the ring because it sees the enormous potential for the future, even if it takes Americans a few years to acclimate to a Japanese manufacturer swapping paint with teh big three. Again, a smart step for Toyota and NASCAR. Who doesn't want to see the Toyotas get smoked by the Fords, Chevy's and Dodges?

Until the IRL/CART split, I was a dedicated fan of the genre, but it was just too confusing to keep up with who went where. Some of my favorite drivers were in one and other in the other. The racing just wasn't the same anymore. I understood the reasoning behind the split, but it wasn't enough to hold my interest.

F1 is truly the most awesome form of auto racing(Istill say the most awesome form of motorsports is Unlimited Hydroplane Racing). It is elegant, graceful and fast paced, but with America's involvement in F1 being so very limited over the years it has just never really caught on here. It's hard to sell the notion of one race a year in the states to a fan base with the opportunity to see 36 races right here in America in cars we actually drive with drivers whos names we can actually pronounce and who we can actually understand on the podium.

That's my take anyway

>>NASCAR has 36 races and, for the last few years, "The Chase", which makes it a ten driver mad dash for the title in the last ten races of the season. Open wheelers have less than half that schedule and the championship has generally been decided by the three quarter point of the season barring unforseen problems.

First of all, "The Chase" now involves the top 12 drivers in the last 12 races.  And, the last 2 IRL championships (this year and last year) have come down to the wire.  After today, only like 4 points separate points leader Scott Dixon and second-place Dario Franchitti with only 2 races left after Dixon's win today at Infineon Raceway in Sonoma. (he held off Helio Castroneves on the final lap).  And last year's champ Sam Hornish won by a tie-breaker (most victories) over Dan Weldon after they ended last season in a tie atop the point standings.

>>Speed Channel is where it's at. Good luck finding even a passing mention on network news sports segments (unless there's a spectacular crash).

Actually, ESPN does show and highlight the races, at least for Champ Car and IRL.  And I saw little coverage of Dario Franchitti's spectacular crashes (both flips) in The Californian.

>>First of all, "The Chase" now involves the top 12 drivers in the last 12 races.

I'd like to correct myself.  It's the last 10 races, not 12.  But it is the top 12 drivers.