What is the main reason politicians spend millions of dollars on advertising during elections?

To influence undecided voters

The reason why "to influence undecided voters" would be the correct answer because this is the reason politicians spend millions of dollars on advertising.

In order for a politician to be successful in an election, they would need followers. The more followers a politician has, the better chance of having people voting for them in the election.

They could have followers already, but they need more followers. The people that they would target in advertisements are the people that are undecided of who to vote for.

They target these people because they want to show the people who are undecided that they're the strongest candidate and they should go for them. This would also give them more followers to vote for them. They're main goal is to influence the undecided that they're the best for the seat that they're running for. It's hard for politicians to change people's minds that are "following" another candidate, due to the fact that they're already have a closed mindset of who they want to vote for, so they aim the easiest to influence, the undecided voters.

lster

Explanation: