[oatmeal1]

The point isn't to win new people to your cause. The point is to get other people who already believe in your cause to overcome apathy and make this cause a primary factor in how they vote. For example, the Free Palestine movement in the US exists mostly among young liberals. The Free Palestine protests that block roads are intended to get young liberals to believe the Free Palestine issue is very important. If they believe it is very important, they won't vote for Biden, who is enabling Israel's war in Gaza. Biden sees the polling and then moves toward a less pro-Israel stance.