Ronald Reagan long ago achieved sainthood in the Republican Party, but perhaps no Republican politician venerates him quite like Scott Walker.

The Wisconsin GOP governor and 2016 presidential hopeful celebrates Reagan's birthday on his wedding anniversary. He launched the current phase of his campaign, the "wreak havoc on Washington" push, at Reagan's alma mater. That isn't going very well, but Walker told MSNBC on Friday that a certain Illinois-born actor-turned-politician also had a campaign that didn't go so well.

"I even thought about [this] the other night at the Reagan Library" -- scene of Wednesday night's GOP debate -- Walker told the hosts of MSNBC's "Morning Joe." "Ronald Reagan was behind, I think, something like eight points six days before the presidential election. So for us, polls are going to go up, they're gonna go down."

But Walker isn't just down by six points. In fact, after spending this spring and early summer as the front-runner in at least one state -- Iowa -- he has since plunged into the low single digits (2 percent in this week's Washington Post-ABC News national poll).

So, did Reagan have to overcome anything like that? Polling from his 1976 and 1980 presidential primary races, which are most comparable to Walker's current race, suggests that Reagan was never this far back.

Craig Shirley, the author of two definitive histories of those campaigns, said that Walker does have a point about the October 1980 general-election polls. Reagan and President Jimmy Carter swapped leads throughout the year, but Carter's landslide defeat obscured just how closely he'd fought the election.

"He and Carter traded the lead maybe four or five times, according to varying sources," Shirley said, "and neither was close to the 270 electoral votes needed for election. It was that fluid. Reagan, in fact, needed the one debate with Carter one week before the election more than Carter needed the debate."

Shirley added: "Reagan won the debate and probably won the presidency as a result. ... Had they not debated, Carter may well have won reelection. It was that close one week before the election."

The story of the primaries is a little more complicated. "Reagan, in fact, was never ahead of Gerald Ford in the national polls in 1976, except just before he announced," Shirley said. "Ford was on one of his many streaks of malapropisms and physical pratfalls, and Reagan was looking good [by] contrast. Reagan indeed went down and up many times in 1979 and 1980 first versus [George H.W.] Bush -- after Iowa for three weeks until New Hampshire."

But in 1980, Reagan never fell as low as Walker is now. A June 1979 Washington Post poll found Reagan lapping the field, with 43 percent support to just 16 percent for then-fast-fading former Texas governor John Connolly. A September 1979 poll, which asked voters how they'd lean if former president Ford entered the race, found Reagan at 29 percent and Ford at just 21 percent.

Metaphorically likening yourself to Reagan can only take you so far.