Seeing the Chicago Cubs in the National League Championship Series is a little like seeing a four-leaf clover — it’s uncommon, but nature does allow it from time to time. And after holding off the St. Louis Cardinals for a 6-4 win on Tuesday night at Wrigley Field, Chicago has stumbled across the rarest of shamrocks — a legitimately dominant Cubs team on the cusp of the World Series.

Three earlier Cubs teams have breathed the crisp, autumnal NLCS air: the 1984, 1989 and 2003 teams. (The league championship series format was introduced in 1969.) Those three squads lost their respective series, but according to our Elo ratings, this year’s NLCS-bound Cubs team is the strongest of the bunch. And even though they’ll cede home-field advantage to either the New York Mets or Los Angeles Dodgers, the 2015 Cubs have the best chance of any of their predecessors at winning the NLCS and advancing to the World Series. Our ratings give the Cubs a 60 percent chance of reaching the World Series; it would be the team’s first appearance there since 1945.

Comparing the NLCS Cubs teams of the past

YEAR W-L NLCS OPPONENT TOP PLAYER (WAR) ELO OPP. ELO WIN % 2015 97-65 Mets/Dodgers Arrieta (8.9) 1565 1529 60.0% 2003 88-74 Marlins Prior (8.0) 1526 1552 42.8 1989 93-69 Giants Sandberg (6.1) 1538 1533 52.7 1984 96-65 Padres Sandberg (8.5) 1549 1523 59.2

We used data from Fangraphs to compare the strengths and weaknesses of the 2015 Cubs to those of past Cubs NLCS teams. For each year that the Cubs advanced as far in the playoffs, we computed the team’s percentile rankings, which grade on a 0 to 100 scale within the season in question (where 100 represents the best in baseball and 0 represents the worst), in six categories. The 2015 Cubs, for instance, had a starting rotation that was better than that of all other major league teams this year but were the worst at avoiding strikeouts (that is, making contact).

How the four NLCS Cubs teams compare

PERCENTILE YEAR CONTACT POWER SPEED DEFENSE STARTERS BULLPEN 2015 0 66 83 97 100 90 2003 7 55 7 76 97 72 1989 44 72 76 68 80 32 1984 12 72 88 60 96 76

Other than their propensity for strikeouts, this year’s Cubs are good at just about everything, possessing a particularly elite defense and pitching staff. Perhaps troublingly, the previous NLCS Cubs teams failed while following a similar blueprint — good power, pitching and defense. But this year’s Cubs appear to be the most complete of the bunch. The ill-fated 2003 team, for instance, had the starting rotation but inferior power and none of the 2015 squad’s speed. The Cubs of 1989 made better contact but had a weak bullpen, and the 1984 edition couldn’t match the current version’s defense.

And so far in the postseason, the Cubs have been leaning even more heavily on power hitting. In Monday’s NLDS Game 3, the Cubs belted six home runs, good for a postseason major league record. Rookies Kris Bryant, Kyle Schwarber and Jorge Soler all contributed to the tally, and Schwarber homered again on Tuesday. (His home run ball still sits atop the newly added video board in right field.) These are the hallmarks of the 2015 Cubs playoff run: young and long. Cubs hitters this year are four-and-a-half years younger, on average, than those on the Bartman-era 2003 NLCS squad.

Game 1 of the NLCS is on Saturday, and while the Cubs will be favored in the series (by Elo at least), no matter who they face, our numbers still say there’s a 40 percent chance they won’t win. So we don’t want to get Cubs fans’ hopes up too much. But fans should at least feel better going into this year’s NLCS than in any of the franchise’s previous three appearances — and that bodes well for the team’s chances of undoing certain 107-year-old droughts.