As noted here before, Scott Walker has a distinct advantage over the rest of the potential Republican presidential field in terms of electability arguments. They have theories and analogies. He’s got a recent track record. They can talk about attracting swing voters or boosting base turnout. He can simply point to three victories in Wisconsin–a state carried twice by Obama–since 2010. Combined with his much-bruited Destroyer of the Unions persona buttressed by other ideological crusades, it’s a seductive pitch for conservatives who want to win but who don’t want to cede an inch of policy or cultural ground to do so.

But anyone with nagging doubts about Walker’s future electability need look no further than 2015 polling on Walker’s standing in Wisconsin. In March Public Policy Polling showed his approval ratio sagging to 43/52, and also trailing HRC by that same 43/52 margin in a hypothetical 2016 matchup. Republicans might well have written that off since PPP is a Democratic polling outfit. But now comes the Marquette Law School poll–a universally respected independent source of polling data often cited by Team Walker in the past to support his public opinion claims–with even worse numbers.

A new Marquette Law School Poll finds Gov. Scott Walker’s job approval rating has fallen to 41 percent, with 56 percent of registered voters in Wisconsin saying they disapprove of how he is handling his job as governor. In the previous poll, in October 2014, Walker’s approval among registered voters was 49 percent, with 47 percent disapproving.

To look ahead to a possible 2016 presidential matchup, former Secretary of State Hillary Clinton leads Walker in Wisconsin, 52 percent to 40 percent.

The bad turn for Walker doesn’t seem to be an accident or an aberration; his recent budget proposals are clearly a factor:

Voters are opposed to a number of cuts proposed by the Walker budget. Seventy-eight percent oppose cutting $127 million from the K-12 public school budget, while 18 percent support the proposal. Seventy percent oppose cutting $300 million from the University of Wisconsin System budget; 26 percent support this.

True, this is just one poll (at least from this particular source), and it might provide slightly better numbers if we were close enough to an election that a “likely voter” screen made sense. But it’s also true that Walker’s three wins were in relatively low turnout midterms (2) and special elections. His “electability” in a presidential cycle, even in his own state, is another matter altogether.

Keep an eye on those Wisconsin numbers as the months go by. If they keep looking like this, other candidates or their flacks may start arguing Walker just doesn’t have it any more. And there’s nothing much sadder than an over-the-hill demagogue.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.