Access Hiddenfield using JavaScript in Content page. Is it necessary to access it by fully qualified name?

I am trying to access a hiddenfield using javascript in a content page.
The hidden field exist in ContentPage. But if I try to access it by ID in getElementById method, it doesn't work and giving me an error.
If I try to access it by full id (i.e. ctl00_ContentColumn_hfTotalItems), it works.. but this looks ugly... isn't there any way to access it directly by ID we have assinged (not rendered.)
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