Since it's possible to specify lining and oldstyle figures I'm hoping there's browser support for tabular numerals with webfonts?##
Font: Brandon Grotesque
Related: Is there a way to specify the use of text or titling figures in CSS?
Simply, yes.
Presently you can use the attribute "font-feature-settings" in its prefixed forms and add "tnum" to the value list (example) to access tabular numerals in OpenType enabled fonts:
font-feature-settings: 'tnum';
-webkit-font-feature-settings: 'tnum';
-moz-font-feature-settings: 'tnum';
Check caniuse to see if the prefixed versions are still needed.
Note, if you are using Typekit to serve your webfonts, make sure to select "All Characters" under Language Support.