In the exact order, with the exact phrasing? Not a chance. This was clearly plagiarism and the brouhaha will continue until the Trump campaign acknowledges it.
If the speech writers started with focus group polling about which phrases play well to the American public, it would be very easy to end up with same values narrative that Michelle used, written based upon similar data.
Having said that, I don't think it reduces the embarrassment to the campaign for not checking the speech against published sources. Just ask any college professor, plagiarism search engines are cheap and quick, and would have caught this in seconds.