Oregonians wisely rejected the very similar Measure 46 in 2006. Here are some quotes (emphasis added) from opposing Voters' Pamphlet arguments that still resonate today:

Oregon Family Council:

If passed, all public policy organizations — pro-family, conservative and liberal alike — would lose much of their ability to educate voters or support candidates. More importantly, voters would be far less educated about candidate philosophies and positions on issues at election time.

Oregon AFSCME:

The reason we are most concerned is because the unfair advantage this will give the extremely wealthy in Oregon elections. This measure will allow regulations on the amount of contributions candidates can collect. Working people who choose to run for office will be forced to spend a great deal of time raising money. On the other hand a wealthy person can still write themselves a huge check and fund their own campaign.

Oregon School Employees Association:

Oregonians know that our freedoms are precious and must be protected. Our freedom of speech protections have served us well for more than 100 years. We shouldn't be fooled into believing less freedom will be good for us.

Planned Parenthood Advocates of Oregon:

This measure goes too far in amending Oregon's Constitution and undermines our freedom of speech protections. This measure exempts ALL future actions of the legislature or ANY ballot measures regarding election contributions and expenditures from the Oregon Constitution's freedom of speech protection. Our rights are too precious to be surrendered without knowing what those future measures might do to limit our freedom of speech.

Oregon Right to Life:

Currently, you can let your voice be heard by supporting any political organization with your time and money. [This measure] will change the Oregon Constitution and allow others to regulate how much you can contribute to your preferred candidates and political organizations.

Keep Oregon's freedom of speech protection in the Constitution, away from extremists and out of the hands of the legislature.