The short answer is "no", there is no general way to do this. To quote from The Mac OS X Human Interface Guidelines

Click-through is not a property of a class of controls; any control, including toolbar items, can support click-through. This also means that you can support click-through for any subset of items; you do not have to choose between supporting click-through for all items in a window or none.

[...]

Avoid providing click-through for an item or action whose result might be dangerous or undesirable. Specifically, avoid enabling click-through for an item that:

• Performs a potentially harmful action that users can’t cancel (for example, the Delete button in Mail)

• Performs an action that is difficult or impossible to cancel (such as the Send button in Mail)
• Dismisses a dialog without telling the user what action was taken (for example, the Save button in a Save dialog that overwrites an existing file and automatically dismisses the dialog)
• Removes the user from the current context (for example, selecting a new item in a Finder column that changes the target of the Finder window)
• Clicking in any one of these situations should cause the window that contains the item to be brought forward, but no other action to be taken.

Note: Programmatically, supporting click-through is a matter of disabling click-through for items that should not provide it. This is because click-through is supported by default in all Cocoa controls.

In other words, click-through is enabled (or not) on a control-by-control basis with thoughtful consideration as to the consequences of allow it. It is not a general property of a window or the window manager.

The short answer is "no", there is no general way to do this. To quote from The Mac OS X Human Interface Guidelines

Click-through is not a property of a class of controls; any control, including toolbar items, can support click-through. This also means that you can support click-through for any subset of items; you do not have to choose between supporting click-through for all items in a window or none.

[...]

Avoid providing click-through for an item or action whose result might be dangerous or undesirable. Specifically, avoid enabling click-through for an item that:

• Performs a potentially harmful action that users can’t cancel (for example, the Delete button in Mail)

• Performs an action that is difficult or impossible to cancel (such as the Send button in Mail)
• Dismisses a dialog without telling the user what action was taken (for example, the Save button in a Save dialog that overwrites an existing file and automatically dismisses the dialog)
• Removes the user from the current context (for example, selecting a new item in a Finder column that changes the target of the Finder window)
• Clicking in any one of these situations should cause the window that contains the item to be brought forward, but no other action to be taken.

Note: Programmatically, supporting click-through is a matter of disabling click-through for items that should not provide it. This is because click-through is supported by default in all Cocoa controls.

In other words, click-through is enabled (or not) on a control-by-control basis with thoughtful consideration as to the consequences of allowing it. It is not a general property of a window or the window manager.