CHICAGO -- Dallas Keuchel has been a part of the Braves organization for just a few weeks. But the early impression has given him a sense he is part of team that rivals some of the great Astros clubs he was on over the past few years.

“It’s a complete team,” Keuchel said. “I know a thing or two about complete teams. This group really excites me, day in and day out.”

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There has certainly been a genuine sense of excitement surrounding the Braves, who have MLB’s second-best winning percentage since May 10. This is an energetic club that has been strengthened by Keuchel, who teamed with a much-improved bullpen to parlay two homers into a 5-3 win over the Cubs on Wednesday night at Wrigley Field.

“We show up ready to go every single day,” said catcher Brian McCann, who was Keuchel’s teammate on the Astros the past two years. “I think when you have that quality, it trumps everything else. We have the hunger to compete, to win and to be great.”

As the Braves have won 30 of their past 43 games, including 18 of 24 this month, they have gained a 5 1/2-game lead in the National League East and looked much more formidable than they were when they won the division last year.

At the halfway point on the schedule, the Braves (48-33) are a win ahead of last year’s pace and eons beyond where they were on May 9, when they were 18-20 and given a 31.8 percent chance to make the postseason by FanGraphs’ projections.

That percentage sat at 94.8 after Wednesday night’s victory.

“We’re in first place,” Nick Markakis said. “We’re exactly where we want to be. You’ve just got to keep taking it day by day and keep plugging away.”

Here are some of the key reasons the Braves are heading toward the All-Star break with genuine optimism.

Power barrage

With McCann’s second-inning solo shot and Markakis’ decisive three-run shot in the fourth, the Braves increased their MLB-leading June home run total to 50. They have 126 this season, which is three more than the 2003 club had at the midpoint on its way to a franchise-record 235 home runs.

Freddie Freeman (14.86), Ronald Acuna Jr. (16.74) and Josh Donaldson (18.27) all have an AB/HR rate that ranks among the top 20 produced by a Brave this century. Rookie Austin Riley doesn’t rank among the qualifiers, but he’s homered once every 12.58 at-bats since debuting on May 15.

Much has been made about the transformation this offense has made since Acuna moved back to the leadoff spot on May 10. But Riley’s arrival five days later has also been a big factor.

Bullpen evolution

With closer Luke Jackson and setup man Anthony Swarzak unavailable on Wednesday, Jacob Webb, Sean Newcomb, Touki Toussaint and A.J. Minter combined to keep the Cubs scoreless after Keuchel completed his 5 1/3 innings. Minter retired the only four batters he faced after entering with two on and two outs in the eighth.

This kind of combined effort would have been deemed rare back on May 9, when Minter was demoted to Triple-A and the Braves’ bullpen had a 4.46 ERA through the first 38 games. But this relief corps has evolved and proven to be one of the team’s strengths, producing an MLB-best 2.89 ERA since May 15 (39 games).

“Where we were two months ago and where we are now … you look down there and a lot of guys have gotten a lot of different opportunities,” Braves manager Brian Snitker said. “They’re just getting valuable experience every time they go out there, and they’re doing a great job.”

Jackson has proven serviceable in the closer’s role, but the biggest improvement with the bullpen has come via the depth gained with Newcomb’s transition to reliever and the May 20 acquisition of Swarzak, who has allowed just one run in 16 2/3 innings for Atlanta.

Still-evolving rotation

Kevin Gausman is on the injured list, attempting to recover from three ugly starts that may eventually lead him to the bullpen. And Mike Foltynewicz was optioned to Triple-A a year after earning his first All-Star selection.

So it’s easy to see why the Braves were willing to give Keuchel $13 million to make approximately 18 regular-season starts. The former American League Cy Young Award winner has struggled to find consistency with his breaking pitches through two starts, but he’s looked like he might be a solid co-anchor with Mike Soroka, who ranks second in the Majors with a 2.07 ERA.

If you want to know how good the offense has been, the Braves have lost just six of 24 games this month with their rotation posting a 5.50 ERA. There will be a push to add another starter before the July 31 Trade Deadline, but the signing of Keuchel has already provided some much-needed stability.

“The first two starts, everything has been positive so far,” Snitker said. “He’s just going to keep getting better.”