Android action bar (Sherlock’s action bar) - position the drop-down counter all the way to the right

Is there a way to reposition the dropdown counter in the action bar?

I found this style for a drop down list:

    <style name="Sherlock.__Widget.Holo.Spinner" parent="Widget">
    <item name="android:dropDownSelector">@drawable/abs__list_selector_holo_dark</item>
    <item name="android:popupBackground">@drawable/abs__menu_dropdown_panel_holo_dark</item>
    <item name="android:dropDownVerticalOffset">0dip</item>
    <item name="android:dropDownHorizontalOffset">0dip</item>
    <item name="android:dropDownWidth">wrap_content</item>
    <item name="android:gravity">left|center_vertical</item>
    <item name="android:spinnerMode">dropdown</item>
    <item name="android:clickable">true</item>
</style>

... but how can I make this counter all the way to the right of the action bar? Now it looks like this ....

I would like the counter to come close to the right side of the action bar.