Marco's father - and car owner - Michael Andretti was just as delighted with the win as his son, and quipped "I'm beginning to really love Iowa!
"It was a big win for us for sure," Michael continued, going on to refer to the turbulent few weeks since the disastrous Indianapolis campaign for the team. "I think a lot of people were really pounding on us and thought we were down and out, but I can tell you this team has got tons of fight in it, and we are never out. We got together and made a few little changes in the team, and everybody just rallied and everybody worked their butts off, and here we are. I'm just proud of everybody on this team.
"I think it's huge, and hopefully we can get the momentum going here. It's always nice to get a win. I think it just lifts everybody within the team and hopefully we can just now ride this momentum. I'd love to see him winning in Toronto. That would be just huge."
"Dad is like a god up there, seven wins!" added Marco. "But I'm looking to make my mark up there, for sure."
The return of an Andretti to victory lane after such a long gap is indeed a hugely popular result everywhere and not just in Canada; and it capped what is possibly the rejuvenated IndyCar Series' most successful weekend outside of Indianapolis since Randy Bernard took over as CEO.
"I think it's going to be a popular win, and I think we need to get him up there winning more than just this one," said Michael Andretti. "And hopefully Graham [Rahal, son of former champion and Indy 500 winner Bobby Rahal] will get up there, too, and get a little rivalry going. I think that sort of thing is always good!"
"We had a packed house tonight," said Marco. "It was good to see. I'm glad we could put on a bit of a show anyway." And the Iowa Speedway did indeed look close to its 30,000 capacity for the thrilling night's entertainment, compared with the deeply disappointing turn-out at Milwaukee the week before which saw the stadium attract only around 15,000 fans or a third of the facility's capacity.
Things also looked good on the TV front, with US cable network Versus reporting a 35 per cent year-on-year increase in viewers, as the coverage once again was boosted by the addition of Dan Wheldon to the commentary team, and a striking if somewhat stilted and rushed first attempt at a BBC F1-style "grid walk" before the race.
In fact the evening race was such an overall hit with everyone concerned that there was immediate talk that perhaps it would host next year's "double header" style event, staged this year at Texas but with problems related to the timing because of the June heat in Texas that meant the race didn't end until almost midnight on the East Coast of America.
But such advance plans are for another day. In the meantime, IndyCar is just celebrating the return of one of its most famous family names to the top of the box score.