Dixon finished second to Will Power at the ‘Tricky Triangle' as Newgarden came home in fifth position, and the New Zealander is now 52 points off the top of the table, in fourth in the standings.
There are three races remaining this season, with 50 points on offer for a win in the first two, 100 for the finale, and bonuses for pole, leading at least one lap, and leading the greatest number of laps.
While the five-time and current champion is therefore just over a standard race behind, and would also have to usurp Alexander Rossi and Simon Pagenaud, Dixon pointed to the circumstances in which he won his fourth title as reason to remain hopeful.
Dixon also pointed to the return to Laguna Seca, which has not hosted a top level American open-wheeler race since the 2004 CART event, for the finale as a wildcard.
“I think, honestly, until you're out of it, you're never really out of it,” said the Chip Ganassi Racing (CGR) stalwart.
“I don't know what the points gap was going in '15 for us, behind Montoya. (But) It's definitely achievable from the point deficit right now.
“There's still a long ways to go. I think the next two will be pretty interesting. St.Louis (Gateway) is going to be a lot of fun. Then Portland will be interesting.
“For a lot of us, too, it was interesting to get back to Laguna for a while,” he added, referring to a private test there in February.
“Some teams struggled more than they thought they would. Laguna will be a pretty interesting race with double points.”
While Dixon is clearly a hunter at present, a contrast to 2018 when he took over the series lead midway through the campaign and continued to tighten his grip, there are similarities to last year.
Then, he finished top three in six of the last nine races of the season and fifth in another two of those.
From the most recent four races, Dixon has a win and three second places, a run which has seen him gain 42 points on Newgarden, who has been on top of the table after all but one race so far this year.
“Last year, we took the lead of the championship at Texas and carried it through, which was very different, felt a lot different. It's a lot more stressful that way,” said Dixon.
“But, no, I think the team, even Dario's (Franchitti, former team-mate, now CGR adviser) championships were similar to that scenario. The start of the year, midway you're kind of there, thereabouts, but really came on in the latter parts of the year.
“It's (champion) the best over the full year. Sometimes that down part creates determination not just in yourself but also in the team.
“It also allows you a little bit of difference, maybe in strategy can you take more risks, you can go for race wins. If you get on a roll, it just starts to feel good for everybody and it kind of continues a little bit longer.
“I don't know, there have been many championships won many different ways.
“Josef took the lead for the championship the first race, so we'll see.”
The Gateway event takes place on August 23-24 (local time).