As it is now, Web companies not only have the ability to provide diabolically precise demographic targeting to political campaigns, they can also make such offers exclusively.
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Web companies use this advantage to assist those politicians that they prefer for office. 
( ( Web companies ) ( ( use ( ( this advantage ) ( to ( ( assist ( those politicians ) ) ( that ( they ( prefer ( for office ) ) ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNP Web) (NNS companies)) (VP (VBP use) (S (NP (DT this) (NN advantage)) (VP (TO to) (VP (VB assist) (NP (DT those) (NNS politicians)) (SBAR (IN that) (S (NP (PRP they)) (VP (VBP prefer) (PP (IN for) (NP (NN office)))))))))) (. .)))