Connection Between Optical and VHE Gamma-ray Emission in Blazar Jets

MAGIC has been performing optically triggered Target of Opportunity observations of flaring blazars since the beginning of its scientific operations. The alerts of flaring blazars originate from Tuorla Blazar Monitoring Programme, which started the optical monitoring of candidate TeV blazars in 2002 and has now collected up to eight years of data on more than 60 blazars. These ToO observations have resulted in the discovery of five new VHE γ-ray emitting blazars (S5 0716+714, 1ES 1011+496, Mrk 180, ON 325 and B3 2247+381). In addition part of the discovery of BL Lac and the discovery of 3C 279 was made during a high optical state. In this contribution we present a detailed analysis of the optical light curves which are then compared to MAGIC observations of the same sources. We aim to answer the question: 'Is there a connection between optical and VHE γ-ray high states in blazars or have we just been lucky?'