The statistics say they have scored more runs and have more come-from-behind victories than any other team.
Doubts linger because the Cubs are only 10-13 on the road, where they play 23 of their next 32.
"After this next month or so, when we get through this next stretch of [road] games, we'll know exactly where we're at," manager Lou Piniella said as his team prepared to head west to play the Padres.
"We'll see what the road brings, but I have a pretty good feeling."
His team should feel good after pounding the defending National League champions four straight times. Mark DeRosa knows that feeling, having played with perennial championship teams in Atlanta. He has said before that the Braves knew they were going to win.
"I think we've reached that point," DeRosa said. "At least I feel that way. When I was with Atlanta some of those years, I just saw the way those guys carried themselves. When you put on that jersey, we just expected to take two of three or three of four. If it didn't happen, it was [amazing]. And that's the way I feel about this year."
On a sunny but chilly day, the Cubs capped their homestand with starter Sean Gallagher raising his record to 3-1, Kerry Wood saving his 14th game and Jim Edmonds showing that he wants to stay. Edmonds socked a triple and a double and walked with the bases loaded, adding to his 3-for-4 game the last time out.
"I'm seeing the ball better, my head is not moving as much and I feel quicker," he said. "This is what it's supposed to feel like. I worked really hard this winter to get back and play. I was disappointed how the year started. Hopefully it will turn around."
Aramis Ramirez drove in the first run with a single. Then Edmonds pulled the Cubs into a 2-2 tie with a fourth-inning double. An error that followed gave the Cubs the lead.
Edmonds' second RBI came on the walk in the fifth inning and was the game-winner, though Alfonso Soriano clubbed his 13th homer in the sixth.
That was enough for Gallagher, who struck out a career-high eight in 52/3 innings, and four relievers.
"You can go out with all the confidence in the world knowing this team is going to score runs," Gallagher said.
Said Piniella: "This kid's got good stuff. He gets after it out there."
The result was the Cubs' 21st home victory in their last 25 games, and it sent a season-high 41,730 fans home in delight.
"The fans should get excited," Piniella said. "This is a fun team to watch. They play hard every day, and you get your money's worth.
"[But] to be talking about the best team in baseball or the best record in baseball on the first of June, I think it's overkill. We're only a third of the way through the season, and a lot of things can happen."