Lets say A webpage has been ranked no. 1 in google for a particular keyword due to its strong online and offline page optimization; by building strong backlinks and now it stand NO.1 in all the major search engines such as yahoo, google , msn etc. Now building more backlinks for that webpage will make any more better top positons in SERPS or coz it already stand on no.1 spot or maybe it could be ranked high for some other keywords . what are the possibilties. explain.
If your website has reached the number one spot for your most preferred keyword, you should continue to optimize the site and build backlinks for two reasons: 1) To keep your position and make it harder for competitors to overtake you. 2) To improve your position for other keywords.
the possibilities remain on the anchor text I think. I heard of someone talking about the uncertainty of this method (anchor text with keywords) but I'm not to sure about it.
I think you should on one hand keep building like to the site. And at the same time put some effort on the inner pages (which focus on other keywords). It is good to rank well for one keyword. However, it will be even better if your inner pages can rank well with other keywords.