ComboBox of CheckBoxes not checking item when row clicked

I've got a combo box of checkboxes that allow the user to select multiple temperature bands. When the users clicks on the checkbox, or the text directly next to the checkbox, the boxes are checked correctly, and my combobox text updates to add/remove the selected temperature. However if I check in the area of my combobox drop down to the right of the text, the checkbox isn't toggled, and instead I get namespace text in my combo box.

Here's my XAML

<ComboBox x:Name="cbDegrees" ItemsSource="{Binding m_DegreeValues}" Text="Degrees" IsEditable="True" IsReadOnly="True" Grid.Row="0" Grid.Column="0" Margin="5" Background="Gray" >
                <ComboBox.ItemTemplate>
                    <DataTemplate>
                        <CheckBox Name="chkDegrees" Content="{Binding Name}" Checked="Degrees_CheckBox_Click" Unchecked="Degrees_CheckBox_Click"  IsChecked="{Binding Path=IsSelected, Mode=TwoWay}">
                        </CheckBox>
                    </DataTemplate>
                </ComboBox.ItemTemplate>
</ComboBox>

I would like to have the checkbox toggled when I click anywhere in the line item for the temperature.