Here’s a pretty clear sign of which way the politics are moving in the fight over Obama’s decision to employ a recess appointment to install Richard Cordray as head of the Consumer Financial Protection Bureau.

Senator Scott Brown — who’s facing a stiff populist challenge from Elizabeth Warren, the creator of the agency — has now come out in support of the move. His statement, sent over by his office:

“I support President Obama’s appointment today of Richard Cordray to head the CFPB. I believe he is the right person to lead the agency and help protect consumers from fraud and scams. While I would have strongly preferred that it go through the normal confirmation process, unfortunately the system is completely broken. If we’re going to make progress as a nation, both parties in Washington need to work together to end the procedural gridlock and hyper-partisanship.”

Other Senate and House Republicans have denounced Obama’s recess appointment of Cordray as an act of tyranny and worse. Scott Brown’s Massachusetts colleague, Mitt Romney, just released a statement calling the move “Chicago style politics at its worst.”

Yet Scott Brown is now breaking decisively with his fellow Republicans, defending the recess appointment as necessary to break through partisan gridlock in order to “protect consumers from fraud and scams.”

Brown, of course, is being challenged by a candidate who may be more identified with protecting consumers against Wall Street than anyone else on the national stage right now.

Brown has evolved on the issue. In July of 2010, he strongly called on Obama to refrain from making any recess appointment to the CFPB, arguing that it was the responsibility of the Senate. More recently, after the Warren challenge heated up, he called on fellow Republicans to support Cordray to head the bureau, but still continued to insist the Senate must appoint him. Now he’s backed Obama’s massive “power grab.”

This seems like as clear a sign as any of just how toxic the politics of this fight could prove for moderate Republicans — not even the “Obama as tyrant” line can carry the day this time — and who is winning the argument over Wall Street accountability and the middle class.