You can mass email bloggers.
Using automated tools, you can auto-post comments onto "relevant" posts.
You can buy email databases of "influencers".
You can perform a basic search on LinkedIn and mass email your top 100 targets.
But 99 out of 100 times, your "personal message" in the social channels will be less than relevant, inauthentic and far from effective.
What do these tactics do for you? What do they say about you? Does it say that you get it, understand social or sincerely desire a relationship? Does it make your message meaningful? Or are you just spamming in a more personal (social) channel?
Technology does not replace human relationships and human communications. It enables it.
Great ideas and strong strategies will succeed. Junk mail is still junk, no matter the platform.