The Global Firepower database published earlier this year provides an interesting perspective on the relative military strength of the former-Soviet Union (FSU) member states bordering Russia as compared to Russia. The contrast is so sharp that any of the FSU countries would almost certainly be unable to defend themselves from Russian military advancement without the direct involvement of NATO or other allied forces.
The Baltic States, Georgia, and Ukraine combined spend fifteen times less on defense than does Russia. While military expenditures offer only a simplistic cross-country comparison - obscuring differences such as procurement systems and how related industries are supported by each government - the data in this case does show a correlation with smaller armed forces and limited resources. For example, the active military manpower of the Baltic States - comprised of Estonia, Latvia, and Lithuania - is 25 times less than Russia's, and the States have no tanks (vs 15,400 in Russia), no fighter jets or other interceptors, and only small coastal Naval defense crafts.
Based on recent history and official statements, NATO has a standing, unambiguous readiness to assist and thereby almost certainly influences Russia's offensive military plans. Compared to joint NATO forces, the Russian army of today is considerably weaker, even with allies from the Collective Security Treaty Organization.