Toronto ? Paul Tracy’s whole season may be riding on his hometown race.

The defending Champ Car World Series champion, 46 points behind leader Bruno Junqueira going into today’s Toronto Molson Indy, figures he can’t afford to fall any further behind as the season nears its halfway point.

“This is my hometown, and this is the biggest race of the year for me,” said Tracy, who will start second in the 18-car field. “It always has been my biggest race, and it always will be.”

More so this year, though, as Tracy tries to climb out of a hole for which he at least partially blames nemesis Alex Tagliani. In the race June 20 in Portland, Ore., Tracy became irate, claiming Tagliani held him up for a dozen laps and cost him a shot at winning. Last week in Cleveland, Tracy got caught up in a crash involving Tagliani and rookie Justin Wilson.

Although replays showed that Wilson appeared to be at fault, Tracy has continued to blame Tagliani for “making it very, very difficult for me to have a real shot at the championship.”

The two have sparred this week, even writing opposing columns in two Toronto newspapers.

But Tracy likely won’t have to worry about his fellow Canadian today, at least early in the race. Tagliani will start well behind Tracy in ninth.