Newline without double spacing?

In some cases, I’d like to enter a newline (line break) without causing my text to double space.

I have installed the Ultimate TinyMCE plugin, and used it to make the text in question smaller than the body (without any newlines) text above it.

I can see that this topic has been discussed extensively on the web, but the suggestion to “SHIFT Enter” does not work for the smaller text. The double spaces remain.

The WordPress HTML view does not show the <p> that is apparently being inserted each time I hit Enter.

I formatted my text in Word, and and tried the “Paste Word” function, but that didn’t work at all.

I realize I’ll need to learn to muck around with the .css files, but right now I’m hoping there’s a quicker fix.

Suggestions appreciated. If I should be editing in some other editor and just pasting the final product into WordPress, that’s fine, let me know – but I’m on a Mac, so can’t use the Windows editor everyone loves.

Thanks.