"Forget Pro Bowl, I'm going to make him president of the United States," the Pittsburgh Steelers quarterback said with a laugh.
When asked what Miller's platform would be, Roethlisberger -- who installed himself as Miller's campaign manager -- kept it simple.
"You should be tough, be tough like Heath," he said.
Forgive Roethlisberger for his exuberance, and never mind that at age 30 Miller is still too young to run for the White House. Considering the way Miller has quietly and responsibly carried himself through his steady eight-year career, it's no wonder Roethlisberger wouldn't mind having his good friend running the country.
Not that Miller would consider it. Running for president would require bringing attention to himself, something Miller has avoided with the same kind of agility that's made him one of the league's most consistent tight ends for the better part of a decade.
Even now, in the midst of perhaps his finest season, Miller seems just happy to do his part for a 3-3 team still searching for a rhythm heading into Sunday's game against Washington (3-4).
Listen to Miller talk and you wouldn't think he's second on the team in receptions (31) and tied with New England's Rob Gronkowski for the NFL lead for touchdown catches by a tight end with five. On paper -- and on the field -- it looks like Miller is in the midst of a career year. Not that he's paying attention or anything.
"You can look at the stats and make determinations based on that but I feel I'm the same player I've always been," Miller said.
One that may finally be stepping into the spotlight whether he likes it or not.
Roethlisberger has always considered Miller a "security blanket" since the day the Steelers selected him in the first round of the 2005 NFL draft. The bond between the two appears stronger than ever, particularly around the goal line.
Miller's touchdowns this season have all been nine yards or less, a tribute to the way Miller can get his 6-foot-5 frame to work within confined spaces. In last week's 24-17 win over Cincinnati, Miller cut across the middle, hauled in a fastball from Roethlisberger then absorbed a couple of shots before coming down with the ball to help the Steelers tie the game late in the first half.
"He catches it with his hands, he gets hit by a bunch of guys, holds on," Roethlisberger. "You've got to enjoy throwing to a guy like that."
And while Miller often doesn't show it, he enjoys playing like that. His post-touchdown celebrations are often muted affairs. He's only too happy to leave the turf-thundering spikes to Gronkowski.
Every once in a while -- particularly if he thinks the Steelers need a lift -- Miller will provide a glimpse of what's going on underneath the helmet.
On the road with the season at a critical point against a division rival turned out to be one of those times.
Standing in the end zone in hostile territory, Miller looked up into the crowd and flexed just before getting mobbed by his teammates. The uncharacteristic outburst didn't go unnoticed, even if Miller sheepishly and sincerely insists it wasn't planned.
"It's cool to see him show emotion because he's such a reserved guy," rookie tight end David Paulson said. "When he makes plays he gets the whole team going ... he does everything right."
The Steelers are relying on that leadership more than ever. When injuries to the offensive line forced Pittsburgh to start rookie Mike Adams at right tackle last week against Cincinnati's aggressive front seven, the team lined Miller up to Adams' right early in the game to take some of the pressure off until Adams could settle in.
Perhaps it's no coincidence most of Pittsburgh's season-high 167 yards rushing came right behind Miller.
It's that dedication to being all facets of his position that led Roethlisberger to call Miller "maybe the best teammate I've played with at any level."
That selflessness, however, has rarely led to personal accolades. Miller went to the Pro Bowl in 2009 but has spent the majority of his career in the shadows of players who have put up gaudier numbers.
Miller would appreciate a trip to Hawaii but hopes he doesn't get to go if selected. He'd rather be getting ready for the Super Bowl the last weekend in January if given the choice.
It's typical Miller, who is making a case that he's the best tight end in franchise history. His next touchdown catch will tie Elbie Nickel's team record for scoring grabs by a tight end (37). He's already third on Pittsburgh's all-time reception list (368) and should move into second at some point if he continues to stay healthy.
Miller shrugs off his ascension up the ladder, calling it merely a byproduct of longevity.
"If you stick around long enough, I guess those things come," he said. "I've been here awhile and fortunately I've been with a good quarterback for all those years so I think that counts for a lot."
So does working with a metronome-like consistency that sometimes gets taken for granted, just not by his quarterback, who believes Miller the best player at his position in the NFL.
"Absolutely," Roethlisberger said. "People are going to argue with numbers, but all around tight end, no doubt about it."