Yes, the election is slightly rigged by all of the political maneuvering. In previous elections, there have been attempts to suppress the black vote. In this election, attempts to suppress the black vote may happen again. Furthermore, suppression of the working class and below vote has taken place in the past and may happen again.
Vote suppression is a big indication the election is rigged and that only a certain powerful few have any real say in which politicians get elected to public office. This undermines the idea of democracy, and it erodes any attempts at having a fair election where the people choose their leaders.
The election is not rigged because by blocking the attempt to suppress votes, the Supreme Court has ensured that all citizens the keep their opportunity to voice their opinion. Had their votes been suppressed, then an argument could be made that the election is rigged. To deny people their voting rights is to void an accurate representation of what the people truly want. The election system is robust enough that the only way to rig an election would be to deny certain demographics their right to vote.
Rigged is too strong a word to use for the election, as there is no evidence that the outcome has been affected so far. There is little question that Republicans are trying to tilt the election in their favor with voter restrictions, as the people affected are mostly poor and minorities who are more likely to vote Democrat. The actual election isn't rigged though.