Jim Harbaugh entered 2018 in danger of losing his widespread support within the Michigan fanbase if the offense continued to waste an elite defense.

After two 10-3 seasons to begin Harbaugh's tenure, the Wolverines slumped to 8-5 in 2017. And he oversaw one of the nation's most pitiful passing games, which ranked No. 109 in yards per attempt and had nine touchdowns and 10 interceptions.

Sure, he'd hand-picked a trio of touted quarterbacks, yet Michigan hadn't seen that recruiting talent translate to the field. Throw in a 1-5 record opposite rivals Michigan State and Ohio State, and unhappiness swirled around the program—which boasted a top-four defense in all three of those years.

But 2018 brought an injection of hope at the position.

The mess at Ole Miss ushered Shea Patterson to Ann Arbor. Rapidly, visions of an undefeated season began dancing in maize-and-blue heads.

Until the season kicked off, that is.

Michigan scored only 17 points during its road loss to Notre Dame. Patterson took a sack that knocked the team out of field-goal range, threw a bad interception and lost a fumble on a potential game-tying drive, which sealed the Wolverines' fate.

He wasn't great. Still, the disappointing loss wasn't entirely on him. That rivalry clash also featured something all too familiar during the Harbaugh era: no running game. Even removing sacks, Michigan mustered 90 yards in 30 carries.

New season, same problems.

Including that matchup, since 2015, the Wolverines had faced 16 teams that ended the season ranked. In those clashes, Michigan held a 5-11 record—with eight consecutive losses—and a combined average of 3.2 yards per rushing attempt. During those 11 losses, that number plummeted to 2.3.

That's why Week 7's beatdown of Wisconsin might be all the more satisfying for the Wolverines and their head coach.

Michigan racked up 320 yards at a clip of 6.7 per carry—the highest average of Harbaugh's tenure against a ranked opponent. It marked the first time since 2014 a Wisconsin defense surrendered that mark to a Big Ten program.

"Our run game really adds another dimension to our offense," Patterson said, per Josh Newkirk of 247Sports. "Our team as a whole, we've really seen the progression of our O-line every single week."

A competent offensive line makes an enormous difference.

The Wolverines have lifted their rushing average from 4.4 to 5.4 and are converting 67.6 percent of all 3rd-and-short snaps compared to 37.8 in 2017. They've ceded 5.1 tackles for loss and 1.6 sacks per game this season after allowing 6.4 and 2.8, respectively, last year.

It cannot be a coincidence the improvement up front has happened since Harbaugh parted with longtime assistant Tim Drevno and hired Ed Warinner to coach the position in February.

No doubt, Patterson's presence has been vital to Michigan's rise.

He's still prone to holding the ball too long, but the offensive line has regularly provided time to throw. That's an enormously positive change in Ann Arbor.

So far, the junior has notched a 69 completion percentage with 8.3 yards per attempt, 10 touchdowns and three interceptions. Harbaugh hasn't overhauled the system, yet he's steadily opened the playbook as the season has progressed.

By no means should Patterson be considered a dual-threat quarterback, but he's mobile enough to keep defenses honest. He broke off an 81-yard scamper against Wisconsin and has had four other runs of 10-plus yards this season.

So, we've seen the offense excel. The challenge is sustaining it, particularly in clutch moments.

The Wolverines have often struggled to successfully run the ball and bleed the clock. Harbaugh teams squandered fourth-quarter leads to Michigan State (2015), Iowa (2016), Ohio State (2016) because they failed up front. Flip those results—those results alone—and the narrative of his tenure looks a lot different.

That's in the past, however. The only way to alter this perception is thriving when the defense knows what's coming. Hammering Wisconsin was a great start, and that performance showed the potential of this tweaked, yet decidedly Harbaugh, attack.

Patterson is an undeniable upgrade. But the Wolverines' move from hopeful contender to legitimate College Football Playoff threat is also a reflection of the offensive line.

Without one, the nation wouldn't care about the other. That combination—finally serving as a complement to a ferocious defense—is helping Michigan return to the championship mix under Harbaugh.

Stats from NCAA.com, cfbstats.com or B/R research. Quotes obtained firsthand unless otherwise noted. Follow Bleacher Report CFB Writer David Kenyon on Twitter @Kenyon19_BR.