With the political election season ramping up, spammers are again using news headlines about the candidates to saturate in-boxes. Researchers have uncovered two new spam clusters with subject lines relating to Barack Obama. At certain points, one of these spam runs accounted for up to 18 percent of all spam, according to MessageLabs. Overall, spam levels for the U.S. in June reached 86 percent of all received mail compared with spam levels at 81.5 percent in the rest of the world. Some U.S. states are more affected than others, according to a recent monthly spam trend report.