Yes, people who attempt to suppress the vote of certain ethnic groups or religious groups should be punished to full extent of the law. Voting is the one of the most important rights that people have. People have died for voting rights and trying to suppress voting is one of the worst things that can be done. No person should tolerate voter suppression.
The attempts at suppressing the votes of certain groups are real and should be identified and strictly sanctioned. It is not only a matter of providing the grounds for more punishment at attempt to suppress voters. The Voting Rights Act should make it easier for groups and individuals that are victims of attempts at, or glaringly prevented from voting to seek redress in a court of law.
The fact here therefore is not only in campaigning for more punishment, it is in making it easier for the suppressed to come forward be identified to have their full electoral rights restored.
Voting is a central tenet of democracy. Any attempt to impede that right is a horrible affront to what our society was built on. Women and people of color, for instance, had to fight tirelessly to gain their right to vote, so anyone who tries to suppress people's voting rights should be adequately punished.
Anybody can claim that certain groups of voters are being suppressed, and can use a variety of different examples to prove it. However, there really isn't much a person can do to actually prove that it is happening, especially to prove that it is being done intentionally. It's hard to enforce and punish something that can't be proven.